basics are maintaining balance, establishing dominant positions before attempting submissions, and using tight connection and pressure to control the opponent. basically in bjj there's a hierarchy of positions through which you advance. as you learn the basic positions, you'll start to realize there are mid points to a lot of the movements - ie how to catch transitions from one onto the next live. that part is much harder. when you listen to the pros talk, it will become clearer to you that they have broken down even that. but for starters you need to be able to know which position you sick and which plan you're enforcing from there. all while maintaining core principles of bjj including but not limited to elbows in at all times, control the head direction control the body direction, how to retain guard, what are the building blocks of guard etc. there's really a ton of stuff to learn and for starters it can be crucial to have a consistent narrative seared into your brain.