How would I go about linking single player spawns from different levels/areas?

Example: Resident Evil games.

In Resident Evil games, each room is it’s own instance/level. You interact with a door to enter/load into the room and the player spawn in front of the door. If you interact with the door again, you will go back to the previous level in front of the door. Perhaps saying, “Linking single player spawns” might not be as accurate as to how the functionality works, but I was looking for an example or a start as to what would be the most proficient, easiest way to do this with many different levels, or even if it comes to having several areas made in one level to teleport to instead of having to open and spawn in many different levels, I am down to do that, however I have zero idea how to go about doing that.

Any help would be appreciated. I am not a programmer, so simple/beginner terms would be nice.

Thanks!