Not sure about the Drive issue, that’s kind of odd. I don’t think I’ve had templates I’ve opened from others show up anywhere except in Recent unless I saved a copy. 
I did want to point out this other sheet though: Add the Savings Budget (Prototype) sheet
It will be effectively replacing the Envelope Budget sheet soon. There’s a migration workflow but if you’re just getting started and you’re comfortable with using something that may not be totally finished it might be easier to skip to it.