If you have chlymidia or another STD can you buy something over counter to help or must you see a doctor? What are ways to prevent bacteria infection?

IF U have an STD. U need to see a doc of the proper antibiotic and cultures can be done to see if you have the chlymidia nad or other stds and you should have blood work to r/o other stds like hiv, hepatita abc, and syph just to make sure and after treatment u need a reculture to make sure it is not resistant, and to prevent u need barrier methods and do not sleep with anyone who may have an std or who has mult par.