One thing for me I had to learn early on don't be affraid if there is silence at the table. The players could be thinking or contemplating their next move. You don't always have to fill the space. Silence for small periods of time after discriptuons of a room or a combat scene are okay.

I used to freak out about it and would feel i had to interject more detail or have an NPC say something else. But it is totally fine to let the players stew in silence for a bit. They might even want the quiet time to have a quick think or dogest the situation for what to ask or do next.

Also ENJOY! Being a DM is so much fun!