Go for it! Professional singer and teacher here.
Practise every day breaking it up into short sessions. You are a sight reader which is a great advantage. Keyboard skills help too.
A recommended weekly/fortnightly session with a singing teacher would be ideal. Not just a pianist but one who knows about vocal technique.
YouTube has lots to offer, but keep away from belt technique or the West End unpleasant nasal sound. Look for a standard classical approach.
Yes to a degree if you can fit it in.
Age wise, be positive. You may not end up at La Scala Milan but daily, and I mean daily, practising will show good results. Domingo carried on singing to his 80s and I sang Carmen in my sixties!
The physical and mental benefits of singing are immeasurable. There is something about singing with a group of people which defies description.
Good luck 🎼