Hello. Welcome to hcm
Tonsils are a part of lymphoid system
which help in building a immune response for infection. Some times they get inflamed and cause problems. They have nothing to do with sexual function. You have absolutely wil have no problem. People who say that have no knowledge about human anatomy.
About operation,it does not have severe side effects and it is safe operation if done in good hands. So you can go ahead and plan for surgery.
All the best