Do submissions just click in place eventually?

For context, I’ve been going for about a year with about 100 classes to my name. I cannot submit people unless they are almost brand new (30 classes or less) and even when I do, they are very sloppy armbars or RNC that almost sort of feel spontaneous.

Is there a point in time where things just start to click?

I’m usually the smallest guy at our gym, 5’7 and 155 LBS. I’m pretty strong for my size, but I get flustered very easily, my cardio is poor and I expend too much energy on dumb things like yanking grips, and I still struggle with my breathing during rolls. I’m trying to remedy that by focusing on my breathing during rolls and doing cardio once or twice a week. I do all the rolls in class too, even if I’m exhausted. (5 rolls for 5 minutes or 6 rolls for 4 minutes)

Anytime I’ve got their back, or I’m in mount/side control/closed guard I cannot for the life of me remember what to do to submit them. I panic.

Is it as simple as YouTubing submissions and trying to implement them in the rolls? Should I be trying to roll exclusively with people worse than me? Are there any basic submissions I should be trying to practice repeatedly during the rolls?

If anyone’s got any advice (especially if you’re a smaller person like me) that’d be great.