What kind of processor do i need to upgrade my laptop?

You would need to determine whether the processor is soldered to the board or if it is a socketed CPU. If it is socketed, look the machine up on the mfgs web site and look at the processors they provided for that model/line. This will tell you which processors will work as upgrades. Be aware that for gaming the graphics processor is much more important and, with the exception of higher end gaming laptops ($1500 + machines) the GPU is NOT upgradeable being either soldered to the board or part of the CPU.

on some laptops it is possible to upgrade the CPU if they are socketed. However it may not be advisable, often the laptop has to be completely dismantled to get to the processor and you risk damaging many of the delicate cables and connectors if you are not used to doing this sort of thing. Also you may be running the laptop outside of the manufacturers intended specs, so a faster processor often generates more heat so the fans may be working harder and more noise, the battery life will be less if there is a higher power draw, the BIOS may not recognise the different CPU.
Most laptop CPUs are not sold direct to the end user only to the trade or manufacturers. As most of these CPUs are not current, then you would have to source off eBay or amazon. Finally most workshops would refuse this sort of work as you would be taking the laptop outside of the recommmended specs.
HTH
David

Processor is soldered to motherboard during manufacturing process. Therefore, it's very hard to upgrade them

Also, laptop processors aren't available on computer stores or online stores like Amazon, eBay, etc. Only desktop processors can be upgraded