The reason I want to use Googe Drive is because the drive files are accessible from a browser on my laptop but also rclone mount as well as a drive app on the Android side.
However Google Drive has one downside for me. Since I don't have the encryption keys locally, they scan files being uploaded (for whatever purpose) and I don't like anyone including automated software scanning my files. So that is why I want to encrypt on my side. Now with the rclone mount command on Linux I can open up the encrypted files in my file manager. So cool.
I will see if Termux will work, but here is someone who basically has tried what I am trying.