Regarding Colmid vs HCG and appropriate treatment check out this sticky: https://forums.t-nation.com/t/hpta-restart-for-trt-w-application-to-gear-pct/211723?u=ksman&source_topic_id=38
…actually…read all the stickies. They directly answer your questions.
For what it’s worth, I’m trying Clomid right now with mixed results. I started taking it to see if I could jumpstart my HPTA systems and begin producing my own T at sufficient levels. It’s working, just not as well as I hoped for.
Being young I think starting with Clomid or HCG is a reasonable first step. Once you introduce exogenous T your body shuts off it’s natural production, which may impact fertility if you’re interested in kids.
I believe a good process would be to first identify, if possible, what’s causing your low T. Is low T a symptom of a larger issue, if so, it may be beneficial to fix the large issue first.
Enjoy the journey…It’s a long and winding road.