To get romance, click the choices with hearts for the character you want. To get friendship, pick choices that the character you choice will like
Spoilers:
Choose to talk to Cedric instead of fighting him, and don't choose the "did you?" choice when talking to him by the campfire if you want his good ending.
If you don't get to know Luke, Cedric, or Wes, you'll end up with Remus. Remus has romance and friendship options as well but he always refuses to go back to the real world with the mc (Kieran). Luke has no romance ending.
After playing every ending of every character, all CGs will be shown in the gallery.