Basically anything meat based is fine. Even high quality kibble they don't normally get, wet food or even use part of their dinner for training. Or you can use lunch meats, cooked meats that haven't been seasoned or hot dogs if you watch the sodium content on all of them. For instance, with my cat (who to be fair is a bit of a glutton) we use samples of Ziwipeak, Acana, Go! Fit + Free but we also have different dog treats. She'll eat almost anything. Meanwhile, one of Transkitty's cats is very specific about what she likes: shrimp. There is literally nothing higher in value to her then a shrimp no matter if it's raw or freeze dried or cooked.
So basically, the animal decides what is rewarding and it's the trainer's job to find what that is.
As far as trick training, it basically comes down to
1) being clear and consistent with your reward marker (the sound used to tell the animal 'yes! That thing you just did is exactly what I want!')
2) building up criteria. You don't start teaching in a super busy room when your cat is already tired or is wanting to do something else. You also reward consistently and generously in the beginning so they think it's a fun game. Duration for something like sitting for a full minute also has to be gradually worked up to.
3) breaking down tricks into baby steps. You don't teach 'play dead' by immediately going to rolling onto their backs and you dont teach a dog how to grab a soda from the fridge in one day. It all gets broken down into small, easy steps that are built upon.
4) understanding that each animal is an individual and has their own likes and dislikes. That can be everything from what food they like to what tricks they're willing to do. My cat doesn't seem to like to lay down so I just didn't try to force her to learn it. Animals can also have good and bad days and some days they just may not be interested in playing the game. Also, if the animal seems to be losing interest or getting frustrated, ask for a trick they like and find easy (my cat's is sit) and reward heavily for it then give your 'we're done training's command whatever that may be.
5) keep training sessions short and sweet. Always end on a good note. Duration can depend on the animal but for a baby kitten, I'd probably say 2-3 minutes tops then as he grows it can be extended to 10-15 minutes.
I highly suggest you watch this video https://youtu.be/wT8SQusV8Uk as well as the other videos on his channel. Kikopup is a good YouTuber as well. Yes, they're channels and videos have dogs but their training is based in science that applies to every single animal from macaws to alligators. Even humans learn the same way.