You can still access the game, hatch new Pokemons, and do standard tasks. In a shadow ban, you would not be able to catch any rare Pokemon. It is caused by using GPS spoofing apps, playing the game too much, traveling too fast, or any other suspicious activity. Usually, the ban is automatically lifted in a few hours. Players also can’t take advantage of PokeStops too.
Whenever you would see a standard Pokemon, it will flee away. This is the most basic kind of ban in which you are not able to catch Pokemons so easily. Here are the 4 major kinds of bans that users encounter in Pokemon Go. Therefore, if you are not using a safe tool to fake GPS location on Pokemon Go, then you might get a ban as well. Niantic keeps a regular check on the device and whenever a violation is made, it restricts the user. Though, a lot of people avoid this and use spoofing apps for Pokemon Go instead.
As you know, Pokemon Go encourages people to walk outdoors and catch more Pokemons.