Your post is about coin recovery using the seed phrase and not the wallet file. Or maybe he does not know the difference between recovery using the wallet file and seed phrase. But if it is wallet file that the OP has, he can not use this process to recover the wallet, unless he has the seed phrase.
Advice:
It will be good to always backup the seed phrase also.
I think it is a must for everyone to back up the phrase of their wallet as your advice, especially for op, i think he should have his own phrase, because at the beginning of the wallet creation, he should be able to see the available phrase and back it up immediately. Even so, i have been lookingg for a way to recover it
[1].
[1]
https://www.youtube.com/watch?v=6b3i0uMB75M ( In this video he shows how to recover using seedphrase, but it's not much different from recovering using dat, and it's simpler. )
And, if op has a problem with encrypted passwords in the wallet file, there is also a solution from a previous post by @nc50lc
[2].
[2]
https://bitcointalk.org/index.php?topic=5456549.msg62414506#msg62414506