Find yourself a 'niche' - I am a retired architect so mine is obviously architecture - and learn everything you can about it. The internet resources are there and these days with all the COVID restrictions many of us have more free time than we know what to do with. Then adapt your photography to suit this new area.
Do NOT fall into the trap so many amateur photographers do, of going out on weekend to shoot 'Sunday snaps' (as my stock photo agent said, derisively) and expect to sell those. Nobody does. 99.whatever% end up on free sites like Flickr for the (too many) less-than-ethical publishers, editors and art directors to look at and replicate or (as often happens) 'borrow' with a few modifications to then use as their own work. This happens (a lot!).
#14 said it well when he wrote, anyone/everyone with a good phone can now compete with you for photo work and fast money. Keep this in mind and try to avoid getting too deeply into quick-bucks shooting. I did weddings for six years when I was in high school and university but I hated those events and it was a great day for me when I could finally give the game away. That was in 1972 and I still cringe when asked to take a DSLR to a wedding for 'happysnaps'.
Don't expect riches to flow into your coffers from the first day. With luck, you may make pocket money during your first year. Time and effort expended will (maybe) bring rewards, if you are good at what you shoot and do your study and homework correctly.
This advice will not suit those who want the fast and easy way, but we now live in a new era (about to be post-COVID, we hope) and everything has changed. We must tighten our belts and go with it. Which may mean fewer cameras to play with, less gear purchasing, and 'rationalising' which in my case for the past year has meant disposing of about half my equipment. I was not sorry to see it go as it has been filling up cabinets and photo boxes anyway.
The way ahead in photography is to move forward, not stay in neutral or go in reverse. It has always been this way, but for many of us the sad events of the past year have reinforced this.