You want to start on the newbie routine, the one in the link gprent provided. Once you get there, there is more links for more information. Read and read before you jump into it. Make sure you know what your doing.
I prefer the linear routine approach. PE is not a race. You start off easy and do low amount of PE exercises and increase the intensity slowly until you start gaining. Once you start gaining you should stick with that routine/intensity until the gains stop and then you can take a deconditioning break and/or increase the intensity once again. The newbie/linear routine is safest for learners, but it is possible to get an injury.
Yes, PE exercises can hurt your penis if you do them seriously wrong, my penis is tough so maybe I will change that to just doing them wrong. You should stay away from any advance routines for now. Manual/hands stretching+jelqing exercises have the advantage of how much intensity you can apply. If you feel pain, then your stretching or gripping too hard. Just stay away from doing PE exercises too hard. Since your a newbie, you should also stay away from erect jelqs for now.
2 days on and 1 day off is a normal routine, it’s in the newbie routine so that’s what you should do.
Length gains are easier than girth gains. If you gain with the newbie routine then you obviously stick with that routine/intensity. If you don’t see gains you want to give the newbie routine at least three to six months before trying more advanced routines.
I am still classified as a newbie I made newbie gains and know my advanced routine is working. I got no gains from the newbie routine and many other things that I tried. People are different and will gain differently, I know with my routine I get these positive indicators that no other routine gave. Well I been trying for a long time, until recently I finally found what works for me, so actually I am not a newbie.