Every password you reuse is a domino. One leaks, the rest fall. Hackers literally have a script for this — it's called credential stuffing.
Use a password manager. Bitwarden is free. 1Password is fancy. Apple Passwords is built in. Pick one. Done.
One master password. Long. Weird. A sentence works: 'My cat eats expensive lettuce on Tuesdays.' Try cracking that.