How to create a crypto wallet without getting the first step wrong

I have had an exchange account for a year and I am finally making a real wallet this weekend.

The part that keeps stopping me is that there is no undo. Every other account I own has a reset link somewhere. This one has twelve words and that is it. No support line, no recovery.

So before I move anything in, two things I cannot find a straight answer on. Should I test restoring from the phrase first, on purpose, while the wallet is still empty? And do the email login wallets I keep seeing actually remove that risk, or just move it somewhere I cannot see it?