Okay so i have a group of friends and we hang out a lot, but i just realized than other than my three best friends who I've known for years ive never had an actual conversation (unless i need something or they need something or we need to discuss something serious) with any of the other friends even tho we know each other for months... and i dont know what to do, how should i change that, how do i start talking with them... im really not good at talking unless we share the same interests like anime or something or unless I've known them for years... help

Three friends are already plenty to talk about serious issues.
However, can you really call the others "friends"? If you only ever talk to them when you need something, aren't they more like acquaintances? Otherwise, if you do have some kind of small talk with them, I think that's just fine. If you join their conversations with your friends, I am sure you will find something to talk about.