If so why are there so many threads on testosterone supplements?
Yes it raises T while you take it, but instead of converting into DHT as Testosterone is supposed to… because Finasteride is blocking T–>DHT conversion, all that extra T has to go somewhere… so it aromatizes into Estradiol instead.
Hence warnings and reports about gynecomastia (male breasts), due to men shifting the androgen/estrogen ratio in their bodies to be in favor of Estrogen while on the drug.
As for Testosterone supplements, if you read the FAQ at top of site, you will understand why. For some guys here, after quitting, their T levels drop into the toilet… often with complete loss of libido, impotence, penis/scrotum shrinkage, massive fatigue… nobody really knows why this happens to certain guys (like us, in the minority) after quitting, but it does.
Hence the search for drugs (Clomid, hCG, Tamoxifen) and natural supplements to help restore natural T production, post-Finasteride.
I would suggest you read through this site in more detail as many of your questions will likely have already been answered. Or, do a SEARCH using the search function at top.
Cheers.