How to use token lists in my project like how Uniswap is using in the UI?

I’ve been meaning to use existing token lists in my dapp just like how uniswap must be using these different token lists.

Since token lists at the end of the day are just .json files with a fixed format, i can just import them and start using it but is there a better sdk or way to use these token lists?

Also where can i find token list for other L2 or rollups as well? I can only find token list for ethereum on https://tokenlists.org/