In groups of 3;
2 players one side of net, one at net facing towards baseline, other facing their partner.
One player other side of net initiates ball to player furthest away who plays controlled ball to player facing them at net. That player catches the ball and rolls back to initiator.
Do this 8 times then roate.
New hitters rarely miss because of their arm. They miss because of their feet. Build a reliable approach, then time it with your setter.
When your hitter gets stuffed, five teammates standing and watching is how you lose the point. Good attack coverage turns a blocked ball into a second swing.
Coaches spend hours correcting arms in serve receive when the real fault is almost always the feet. Fix the movement and the platform fixes itself.