Would this be safe/okay to give?

My baby only drinks his formula he’s almost a year old now but I don’t want to give him things with too much sugar I want to keep him as healthy as I can and with teeth to be okay.

He isn’t fond of taking a silly cup yet but we’re trying! I thought maybe I would put some fruit slices with water in his silly cup and try that out?

What do you mamas think?

Safe or stick with milk?

Edit 1: he eats baby food but I’m talking about drink intakes