Yes, implants are safe for most people and your dentist will be able to tell if treatment is safe for you. People who smoke or are have a medical condition (diabetes, compromised immune systems, osteoporosis, etc.) may be at higher risk of failure as these conditions/habits can affect bone quality and the body’s ability to heal (tissues are slower to heal after treatment).
Recovery is typically quite quick, and most people will be able to return to work the day after having a single implant placed. If you have multiple implants placed then you may need to wait a few days before returning to your normal activities, particularly if extra sedation was required.
You should experience few, if any side effects after implant surgery other than the low levels of soreness and swelling that should be expected after any invasive surgical procedure. If a dental implant is placed incorrectly then it is possible to experience numbness or a tingling sensation, or possibly sharp pain. If the symptoms continue for more than a couple of days then you should consult your implant dentist. It is possible it could settle down, but otherwise the implant may need to be removed. This is incredibly rare as risks are minimized through careful planning prior to surgery using x-rays and a CT scan so any nerves and blood vessels are avoided.