My testerone was checked and it was 353. Doctor said that they do nothing until below 300. I had one testicle taken as a child should I be taking testerone? Was perhaps is low all my life, my testicle was taken at 6th grade. I still have the other one.

Double duty. Not necessary. One testicle is doing the job of two.
One . One testis is generally sufficient to produce normal levels of testosterone and induce normal male secondary sex characteristics. A total testosterone > 300 ng/dl is usually considered normal. However, there are other factors that can influence testosterone bioavailability. These can be determined with additional testing. However, in the absence of sexual dysfunction, a lowered sex drive, or other symptoms and signs further investigation is not typically indicated.