i am a new homeowner and never had a pool before. too many problems and don’t know where to begin. initially, i tried shocking the pool and vacuuming. then used algacide/clarifier and vacuuming. cleaned the filter repeatedly when pressure built up at least 10psi.
main problems are:
1.loose plaster is chipping away, like small potholes all over with hairline cracks everywhere
2.black/green algae is present over and under the plaster
3.reddish stains on surface
4.open the main drain cover and no pump to be found

i don’t the funds to pay a professional, so i was planning to do it myself with some help. this is what i was planning to do:
1.drain the pool
2.tsp and acid wash
3.patch plaster holes, since i don’t have enough money to replaster, if possible paint
4.should i clean as much as i can then refill the pool and run chemicals to remove the stains?
5.or is it possible to paint over the algae and rust stains without them reappearing?

thanks in advance for the help