As a hobby flyer, you are to contact any airport/heliport and control tower within 5 miles of where you are flying to notify (not ask permission) them that you will be flying. Usually give them name, contact number, where and when you will be flying. That is all that is required. Tha applies to any airport except some of the biggest and busiest which are Class B. FAA wants everyone to go through the online request process before flying around those airports. In general, airports don't have restrictions, but controlled airspace around them (not all airports have controlled airspace). As described above, that's not an issue for hobby flying. If/when you get your Part107, and you are a long way from thinking about that right now, things are handles differently. Which you would learn about as part of your studying for the Part 107 test. You might want to look at other apps such as Airmap to help you locate and identify any airports around you.