Best way to get trusted blockchain data in DeFi app?

I’m trying to make an investment / exchange DeFi on ICP, i want to connect into all blockchains using any wallet exist, then wait for transaction event and save data into user account…, give them interest for freezing their assets also by inviting people.

Question is whats is the best way for requesting and getting data from blockchain (ethereum, bitcoin, …) into my canister from backend?