How do I train my puppy to walk without a leash/harness. I got a 8 week puppy. When I take her outside I noticed she follows me right beside?

She's EIGHT weeks old, keep her on a freaking leash and keep her safe. Training a dog to walk beside you without a leash reliably is very advanced training and you have to start WITH a leash first, train them to heel, train them to ignore distractions, have bulletproof recall and most would still want to have an e collar for backup- which cannot be used on puppies.
She's getting used to being able to have the freedom to go where ever she pleases with or without your consent, she's running up to strangers, they're giving her attention- which is a reward, and that is reinforcing that behavior to run off if she wants. You need to start giving the puppy boundaries if you ever want the dog you're expecting. Don't punish her for doing that, that'll only make you worse and the strangers better to her. the opposite of what you want- just don't allow it to begin with. YOU are in control, not a 5lb puppy.
Letting her off leash now is beyond stupid, wait a few more weeks and she'll be a lot faster, you won't be able to catch her from running off in time and what happens is completely out of your hands at that point and it can easily be prevented, there's other dogs around as well- that's not safe to let such a young puppy around them, you should NEVER allow a puppy that's not yet fully vaccinated to be in areas where other dogs have been, they can easily catch life threatening diseases. Plus if they get close enough and she gets scared and starts running the other dogs prey drive could kick in and they will chase and maul your puppy. Again, easily preventable. And you're allowing her to be scared of other dogs, which is not good. You need to socialize her PROPERLY in a controlled environment.
You can begin training her to follow you but you'll have to start indoors and use lots of encouragement and reward for her following you, SLOWLY increase the distractions but only in a safe secure area. You're expecting WAY too much right now, you need to let the puppy explore and play a little, but on your terms, not hers. Buy a long line, like 20ft- and let her drag it around while she plays, that way you can step on the leash/lighty tug her back to your direction if she tries to run off. But that's just the very very beginning stages of training, just getting her comfortable with the notion of staying near you, you'd most likely have to take some training classes with your dog to achieve that level of obedience. And we're talking 2 plus years before she's totally reliable- but you can never be too sure, so it's best to have SOME kind of reinforcement, a long distance e collar is typically the tool of choice for people wanting to let their dog off lead. But that's not even an option right now so enjoy your puppy while it lasts and you can focus on having a good dog when she is an actual DOG, she's just a baby right now, so don't overload her on training, and don't allow her to have negative thoughts associated with other dogs, that won't end in a good situation. And don't allow strangers to be an exciting thing, you need to make them as neutral and boring as possible by being the most interesting thing to her. It's all about socializing and introducing things in a safe completely controlled environment.

why????????????? keep your pup on a leach at all times when walking ....now and forever

Your 8 week old puppy has NO Business being off leash in public. None. Heck, pretty much in every city, county, town in the USA there are leash laws.

Would you allow an 1 year old baby to crawl around unsupervised in public?

Your puppy is a puppy, stopping, sniffing and exploringis how they learn. You will not teach an 8 week old puppy to walk off-leash or on leash. At this age, you should be concentrating on housebreaking, teaching him his name.

Heck, he hasn't even finished his second sets of vaccinations yet and has NO business around other dogs. End or story.

You need to keep such a young pup on a leash for her protection, she can dart out into the street, run into a drain or sewer and you will never catch her in time and may never see her alive again.

Once she gets older and isn't such a baby you can work on of leash training. Once she knows sit, stay, down, heel. Her name and come and has a good recall you worry about off leash training.

Would you trust a 6 month old baby human child to play independently out in your front yard? Or a 2 year old toddler to run around the block in his own, darting this way and that totally unsupervised? After all the kid understands the language you speak, you said no running out in the street so he should be obedient at that age? Like when he sees a cool dog, or a fire truck he won't forget your orders would he?

8 weeks old is still very much s baby, she is showing interest in her world, grass, leaves, old wrappers, whatever - off she darts to investigate... You should notice she suddenly stops and want to investigate too right? She doesn't understand the rules nor the dangers of our world yet. Let her grow and mature some, learn about cars and streets, teach her and work with her. Once she gets it snd runs around and doesn't wander off then you can worry about letting her walk leash free with you.

If you decide I'm stupid and your going to do it anyways, keep in mind how long it takes s car to stop IF THEy SEE THE PUP RUN INTO THE STREET. It's not usually in a foot or two. Many puppies and kittens get run over because their owners never thought their pet wouldn't respect the fact the street is dangerous .... Nobody speaks puppy or kitten yet, so they don't understand our rules or dangers.

It's the owner that needs to learn how to train the dog, so sending it away to be trained means it will work for the trainer, but when it gets home the owner will probably do everything wrong and the dog will not respond correctly. Learn how to train your dog obedience https://tr.im/KwWxA

Part of the fun in having a well trained dog is learning to train it correctly yourself. That is also the most rewarding. Some people send dogs away for specialist training, like sheep herding, protection work or gundog training, but even then, that is the lazy way out and good trainers do their own training to get what they want from their own dogs.

However it is always more productive to train your dog under a good instructor, especially if you are not experienced

The law requires the dog to be leashed and under control at all times, you're not above the law.

Keep It Leashed.

Pup should NOT be out on public streets until its had ALL its vaccinations.
Even then, never on the street without being on a leash.
Train your puppy in YOUR yard and Carry her about in public until she is vaccinated.
Also she is still too young to take in too much training.
Lessons must be very short (3-4 minutes) and done 2-3 times a day.

You should not have an 8 week old puppy out on the sidewalk. No dog without all of its vaccinations is safe out there. Distemper, Parvo virus, Corona virus, Parainfluenza, Adeno viruses and MORE are just lying in wait for unvaccinated dogs. It is not time to train her on the streets and sidewalks, yet. You are risking her life.

What kind of dog is it? Because there are many dogs that are born with the sense to follow their leader.

Heya, The best guide that I have checked out was on Brainy paws (i did a google) I bet its the most helpful info on dog training and this type of thing that I have found.