deleting previous scene in transitional room

im using a transitional room set to "dont destroy on load" with one open door and one closed door. when the player enters through the open door, it starts to close and the next scene will be loaded loadlevelAdditive while the first door is closing, when its finished closing, how do i delete the previous scene? (when the next additive scene is finished loading, ill open the next door to the next scene). I know alternatively i could simply loadlevelasync when both doors are closed (and that will delete the previous right?), however the player wont want to wait every time they go back and forth through the room from one scene to another. ive read all the documentation and am just confused about the most efficient method to use.

edit: sorry, i guess everything is depreciated other than the new "loadScene" and "loadSceneAsnyc". So I'd use "loadSceneAsync" to load the next scene in the background, however i don't see anywhere in the documentation where it says how to delete the previous scene or how to check when the new scene is finished loading, only the variable "loadSceneMode" that toggles between "Single" mode and "Additive" mode... am i missing something?

edit: to anyone not getting google results -- Don't search "loadScene", search the API root "SceneManager" instead and all the functions are there. Maybe it was just me lol.