Depends on the camera's sensor, but IMO and assuming you're full frame below 20mm is an ultra wide angle, 20mm-35mm wide angle, 35-85 short telephoto then above 85mm is telephoto.
Ultrawides emphasise foregrounds, and ave a very wide field of view but squish verticals. The 24-35mm range is traditional wide angle territory, as you get to 50mm proportions are more similar to your perception, and above that you get increasing levels of very short depth of field, but the background is magnified (ie the opposite of a wide angle where the background is far away).
Apertures are pretty much a topic in themselves, but f4 and below is good, above that is generally a bit medeocre (except when you get to above 300mm).
There's a bit more subtlety to it but generally: ultrawides for flat landscapes or star photos, wide angles for regular landscape shots and possibly group photos, short telephotos up to 50mm for group shots, full body and 1/2 body shots, 50-200mm sports, portaits, macro some detailed landscape shots, abd above 200mm sports and wildlife, maybe a portrait of a single person if you have room.
There'll be stuff I missed out and it's roughly how I think about focal length. There will be exceptions and you can use focal length creatively so it's not simply a matter of X lens should be used for Y type of shot
You'd probably be better off telling us what camera you have and what you want to photograph, then we can advise what lenses would be good to consider, as the actual answe depends so much on your use case.