Mines been doing lessons since 4 months old (let's be serious, they don't do much at that point!). The teacher only just started them with noodles and occasionally floats once they were 2.5 ish and confident in the water. I've never used any armbands or floatation vests outside of lessons and he is now in the transition class, so i will soon be out of the pool and he'll be swimming unaided (😢). So perhaps just a noodle on their front if you can? X
Mines started with nothing just me holding him, he can now float by himself but likes to use a flat float if available
I use arm band for my little one. And I’m considering too to start swimming lessons from September. I’m not sure if it’s too early.. but I can sit on side for the 30 mins from this age now