It gets even weirder. Depending on where you are the forms can flip. Like you might use usted for your family instead of tu. Also there is vos which is used in some countries like here in colombia.
Awesome, thank you. I know very little about Spanish (some may argue I know very little French too!) but I believe the general formal/informal rules are the same across most Latin languages.
Some of the quirks are cool though, like using the informal when praying to a God because apparently God knows everyone very well 🤔