Trust wallet is open source and Electrum closed source.
Have you mixed things up here? Well, Trust wallet is closed source and electrum is open source, not the other way round!
If you are a newbie, you don't need to know everything immediately. When i started, i was hacked, as many others.
Maybe it's not the best way but if you have under 1000$ in any crypto, i'd say to keep or buy them on binance/coinbase.
Why? Because those 2 are the most trusted, just turn on every 2FA they have and don't brag about it.
You should stop giving advice to users here, especially newcomers who are looking for the best sort of advice, that you were hacked doesn't mean every other newbie should experience that fate. OP don't keep any of your funds in a centralized exchange, be it binance or coinbase, neither of them is safe/trusted to store your funds for you, always use reputable non-custodial wallets to hodl your funds.
Online wallet are the least you could use or get as a recommendation for use because they are not safe for your advantage, you will not have access to the private keys because they are connected to the internet and mostly are mobile wallets,
You've go it wrong here, online wallets are wallets that are connected to the internet, it doesn't mean you won't have access to your private keys, electrum is an online wallet, but you have access to your private keys when you use it.