For the block go to the drop step to the middle of the key to a jump hook.
Make sure you keep your back to the basket. Try not to turn side on.
The key to inside play is being able to keep your back completely to the basket.
Take plenty of shots on both sides with both hands.
Rebounding is the least glamorous thing in basketball and one of the most decisive. It is also almost entirely a habit, which means it is entirely coachable.
Good spacing is only the start. The best modern offences teach players to attack the defence's rotations and play in a permanent 4-on-3 - here is how to coach that read.
The ball screen produces almost half of all professional offensive possessions, yet most teams still teach it as a memorised play. The modern approach trains the read - giving players a framework to decide based on what the defence does, not what the coach called.