A few metres ahead should be enough. You can still look out for glass and potholes.

When you have a nice smooth stroke, you can use your glutes to cantilever your torso's weight against the pedals through the seat. Your arms should be relaxed when you're putting power down.

It's an effort to continue the cantilevering when coasting, so you put your weight back on your hands... sometimes I'll change my grip to near the stem to minimise any unintended steering input in order to save the mental effort of weighting the bars carefully.

Depending on how much muscle memory you have for a bike, it might help to practice riding no-handed. Try doing it by lifting your hands off the bars without moving your body and sitting up.