Which wallet are you using?
seed is everything you need to recover your funds on most wallets.
Just note it down on a piece of paper and recover itusign the same wallet software or another one if they both use bip39 seed..
If you are using some other wallet that generate a wallet file and you encrypt that file, you need to know the password to decrypt it.
I strongly suggest that you use Electrum.org wallet or some other wallet that supports bip39 seed, because it is much simpler to back up and recover it than dealing with files and encryption (in my opinion)
Thank you, I use Electrum.
From all your post and others' so far, it seems that I can recover my wallet with seeds on any other devices.
Backup files and password of backup files are only helpful if I lost seeds, but still have access to backup files & passwords of those files.
Do I understand it correctly.