I love prime lens, and the 50mm focal length is one of my favourites. In my opinion, primes generally offer 3 main advantages — (a) less optical distortion introduced, (b) have wider maximum aperture for those bokehliciuos portraits and finally (c) for the smaller package as compared to zoom lens.
50mm focal length (in full frame) is nifty because you can use it for many types of photography genres. If you’re new, 50mm should be your first prime because it can help you explore these various genres. You’ll be able to find what you like — portraits, street, landscape, etc before investing further in other lenses.
If you’re using a camera with APS-C sensor, you should be looking for focal length of about 35mm. Olympics and Panasonic mirrorless cameras use m4/3 format and the equivalent focal length is 24mm.
All photos below are taken with the manual Minolta MD 50mm f/1.7 with full frame sensor.