Doc Said I Had Low T - At Age 26

So I am a somewhat healthy male, age 26, working hard etc.

I noticed about 5 years ago (20-21) my “drive” for passion has decreased. Later on, I had a test done by the doc and it showed my testosterone levels were 200.

I am unable to maintain a full ED, for example if I am able to obtain one, with me on bottom and she on top, if we switch positions, my erection goes aways 99%.

He said it was because of low T since I was 26, and my test levels were 200 (he said they should be 600).

My question is, what should I look into. I.e hormone replacement? Shots? Herbals?

I can look at a beautiful woman and not get aroused, whereas several years ago if I was in the same position I would be “full steam ahead” aggressive. Now its like whatever.

ANY help or talk would be much appreciated!