Hi Janice, there are very specific acid cleaners JUST for concrete that I would suggest you look into.
Pressure washing the cement will really help it clean up real well.
https://www.hgtv.com/videos/painting-concrete-patio-floor-0126635 Clean well,prep, prime with cement/masonary bonding primer them use cement /masonary paint. Is /has it been previously sealed painted could be lot more prep involved https://www.houselogic.com/remodel/painting-lighting/concrete-painting/
We painted our concrete steps last year and this is what we did: https://www.aratariathome.com/blog/how-to-update-concrete-steps
Thanks a lot. Very helpful answers.