I assume it varies by age, overall health, and possibly gender. So what’s recomended for a male, age 21, with no health problems?
If you are really healthy, not overweight, and without a family history of heritable health problems, you probably don’t need a physical exam other than a blood pressure check. However, you should ensure that you are up to date on your immunizations, understand safe sex, and don’t use tobacco or abuse alcohol or other drugs. See the recommendations of the USPTF at Prevention and Chronic Care | Agency for Healthcare Research and Quality which bases its recommendations on scientific evidence. It would be easy to find people who would recommend additional tests such as cholesterol measurement, testicular examination, etc. This is a topic you can argue over forever.