Op it's a good decisions you have taken upon yourself to in est in Bitcoin but before you make your investments, there are some basic things you need to know their importance before making investment so as not to loss your money along your investment journey. First I'll like you to know that, after buying your coin from an exchange, it's important that you move those coin to a non-custodial wallet for full access and control over your coin. Secondly you need to know the importance of seed phrase, every wallet has a unique 12 word or 24 words seed phrase which are used to import/export your coins to another device or wallet. Without your seed phrase and your wallet device got stolen or damage, your entire holding is gone. That is the more reason why you need to keep your seed phrase safe by writing it on a sheet of paper and try as much as possible to keep it away from the internet, storing it in a safe would be more preferable but if your want to hold a large amount of coins, then you'll need to buy a hardware wallet.