Is there any drug without side effects?

All medications are approved for both safety and efficacy. There exists NO perfect drug without the potential of some adverse outcome, but typically risk/ benefit ratios are appropriate.

No such thing, all drugs should be only taken in the minimum amount for the shortest period of time.

No. Even water taken in excess has side effects to the extent of causing death. It is a matter of addressing risk benefit ratio. For healthy diet: http://www.choosemyplate.gov/., exercise 30 minutes/day, drink enough water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs. Get HPV, Flu and Covid vaccines. Wish you good health!