if a kitten's fearful of you, as my Loki was when we got him due to being feral, then there are a few things you can do.
What I did with Loki was make him a box hide with food and water in it, then placed it where we can still see him enter and leave it, and just let him do his thing.
You don't want to force *any* interactions for the first day or two. Let them get used to your presence.
Once they've had a bit of time to settle, you can try and figure out if they're food motivated.
If you can get a hold of some Webbox Lick-e-lix or similar tube treats, these work great as a way to slowly introduce yourself to the cat.
Poke one in while trying not to get your hand in and let them inspect. Once they start licking at it, you're about to win.
As they're licking away at the treat, see if you can withdraw it slowly but gently from their hiding spot to try and draw them out. Praise them as well the further they come out, but try not to be loud, and absolutely don't make any sudden or unpredictable movements.
Once you're at a stage where they're happy to come out and explore, continue the occasional tube treat tactic but try to introduce gentle petting as well.
Besides this, the other thing that will help you gain their trust and form a tight bond is play.
Kittens have a lot of energy and not many if any places to expend it in a captive setting. Playing with them isn't just a fun thing to do because they go absolutely psychotic over certain toys... But it's actually a requirement for proper exercise and bonding with their new human.