And i want to make a project of building an hardware wallet (something like Ledger )
Please don't make it like ledger
There are much better hardware wallets available today, and I would even say that market is oversaturated with hardware wallets.
Where should i start ? i do not have any idea i saw some video on youtube from people who opened a ledger and saw all circuit there, i think there are 3 important circuit which are microprocess and basics circuit.
If I understand correctly you want to start making commercial hardware wallet device that you want to offer for selling to other people?
In my opinion this is pure waste of time if you are single guy who is starting from zero without any background experience in making products.
You would have to compete with some big players, so this is battle already lost.
It's ok if you are making hobby DIY project, and in that case try to make everything open source and transparent.
(btw i want to build an evm hardware wallet)
More blockchains, means more bugs, more work, and in near future most of shitcoin blockchains won't even exist, or nobody will use them.