I want to wish my friends a good luck, is it ok to say for example "Hey Jen good luck and send my regards to friends"... is this correct or there's a better way of saying this?..
It's correct. It is a respectful way of saying to say hello to her friends on your behalf. Literally "my regards" could give the idea of "my respect" or "my admiration" but has come over time to simply mean greetings in this context.
It's correct if they are your friends also. "Send my regards" means "say hello on my behalf", and so if Jen carried out your wishes, she would say to her friends "L says hello also".
RE:
What does "Send my regards" mean?
I want to wish my friends a good luck, is it ok to say for example "Hey Jen good luck and send my regards to friends"... is this correct or there's a better way of saying this?..