Thank you everyone so much for your responses. You’ve truly opened my eyes to so many aspects I hadn’t even considered before.

Your insights were not only thoughtful but also incredibly helpful. It’s rare to come across such comprehensive answers that cover so many angles, and I really appreciate the time and effort you took to share them.

Each of you has given me a lot to think about, and

I’m grateful for the depth of understanding you provided. Thanks again!

As a first step, I’d like to pick one of the programs to start with:

Cryptomator

gocryptfs (not so Windows-friendly)

GnuPG

VeraCrypt (slower than TrueCrypt, and since it’s offered as a replacement, it makes me suspicious, especially since TrueCrypt mysteriously vanished without providing any explanation. Some people believe VeraCrypt might have backdoors, whereas TrueCrypt’s abandonment perhaps didn’t provide any backdoors.)

TrueCrypt (I have used it occasionally on my Windows PC, although it is no longer updated)

I appreciate your suggestion very much. I wonder what the difference between gocryptfs and others like Trucrypt would be.
Need to search and compare the pros and cons of both, the advantages and disadvantages of each, particularly in terms of security, ease of use, and performance