It’s a snowball effect. The people you see on Instagram and such with thousands of followers didn’t just sign up, post a few pictures, then get that many followers. No artist you’ve ever admired or seen just sat down and churned out great piece after great piece.
If you don’t have an audience, post more often, post things people will like (at first, just to get attention), then build on from there.
Generally nobody cares about ANYBODY getting better. They just want to look at pretty or cool things for like 5-10 seconds then move on. Only other artists take interest in things like process or progress.
The bottom line is don’t give up. Things are excruciatingly slow at first. But like I said, snowball. You can do it.