Clomid or Tamoxifen will boost natural Testosterone levels if your HPTA is functioning properly or you have Secondary Hypogonadism. How much depends a lot on what your current hormone levels are at. Have you gotten blood work? Also, a lot of guys don't feel good on them despite the boost in Test levels. So I would temper your expectations. This will definitely not be akin to running a cycle and unless you are Hypogonadal, you may not even notice the difference.
If you have low t I would not recommend Clomid mono therapy. I was on it for 2.5 years and felt initially better, but progressively worse to the point life wasn't worth living. Even though it raised my test levels from 200's to high 400's. Nothing beats injections for those who are hypogonadal IMO.
I also have some permanent vision changes which stemmed from the long term use of Clomid: constant "floaters" in my eyes.