Hello,
I have some questions and please answer to them by number:

1- Which programming language is good for Blockchain programming? Is Rust-Lang good?

JS Javascript. From what I know and what I'm definitely returning to. It's the most used and famous language in the crypto market. Used by too chains like Ethereum and platforms like Earnbet probably make use of this with its Onchain game.

2- Can making a wallet be profitable? Yes from what I know you can charge a small network fee (probably together with the chain) for transactions.

Any idea welcome.
.

Thank you.