I have wondered for long, if there is anyway to recover my private keys when they get lost or when I don't remember them. Someone advised me to use Gmail and store them as mails then I taught again, what if my Gmail gets hacked. Is this actually the best way to store them or is there any other ways I can store or Keep them safe?
This is the nuance with cryptocurrencies, that without private keys you cease to be the owner of crypto, therefore, in order not to forget or lose them, you should make backups. Of course, in a safe place, and not in the gmail. You correctly noted that mail can be hacked, like any online service, and employees of these same online services can also get access. Therefore, private keys can only be stored offline. Check out this thread -
https://bitcointalk.org/index.php?topic=5389446.0. You can get a lot of ideas about key storage here.