How To Treat Flesh Coloured Bumps On Underside Of Penis?

I have flesh colored bumps on the underside of my penis mostly and when I press on them and squeeze them a string of goop like a black head except not oil, a finer silty string comes out I am uncircumsized and have remembered these bumps for quite some time but haven't spoken to anyone. I am 19 years old and sexually active.