Also depends on your job. Fonctionnaires A of the EN all tutoie each other on principle, it is political.
I wouldn’t tutoie my artisans because it isn’t respectful. Voilà le fond de ma pensée sur les us et coutumes.
And really French people* are very very very rarely offended when foreigners such as you don’t know these things. We don’t expect you to be like us. If a French person in a shop tutoies me I am very surprised and think we haven’t looked after the goats together, if it is an anglophone I am more indulgent, I think I am a fairly typical French person.
*of course some of us are touchy idiots who get offended at anything.