Welcome here! It's absolutely true that investment in Bitcoin most of the time will provide you a huge profit, as because most of the time Bitcoin continues his cycle through which Bitcoin broke his previous ATH and make the new one, so at any price when you bought it, it will return significant amount but the important term is that you should hold it with patience for long time.
I think firstly you should differentiate between exchange and wallet, most of people use exchange for buying and selling and just hold such amount in here through which he can trade, while wallet is mostly for holding coins for long term,

Now there is two type of wallet which are best according to thier security level, like in hardware wallet you should use tezos and ledger while in digital wallet you should use a non-custodial wallet name Electrum..