Encryption works with keys or key-pairs, during the installation a key is generation that is used to encrypted something, in this case your home directory. They require a passphrase to be put on that key, in this case with the Mint 20.2 installation they made it the same as your password at the time of installation. You don't have that password anymore which was used as passphrase so there is no of getting access to your files back. The only maybe option would be if you had some known dictionary password would be to have some brute-force tool try all dictionary words to try and unlock it. Not my area but still chances would still be close to zero. That's the idea of encryption that if someone steals your laptop and it is encrypted they have no way of getting to your files, otherwise encryption would be pretty pointless.
