Need help for Doors-like construct game

So, im trying to make a game like roblox doors/rooms, but im facing some problems, most of them related due to me not knowing how to make a RNG in construct, here´s a list of the things i would like you construct pros to help me with

1: a scipt that, when a door is opened, it loads another totally different room into the game, the shape of the room will be decided by RNG and all types of rooms are loaded in the games memory or in some other scene (the point i want to get is, the shape of rooms for the game to load, shall not ve visible in normal gameplay, but only visible when already loaded

2: a entity spawner, when a room is opened, if the room numbes is higher than the number necessary for the entity to spawn (ex: 30) there will be a chance an entity to spawn and try and kill the player

3: darkened rooms, theese will generate randomly, will be the same as normal rooms, but visibility will be drastilally decreased unless the player has a lighter

What kind of game is this? Platformer, top-down view, 3D first-person view?

1. Generating a room design randomly may be tricky. Especially if you want these rooms to connect properly to each other, and not just teleport from room to room.

2. There is a basic random() expression you can use. For example: random(100)<30 means a 30% chance.

If you need more RNG features, there's an AdvancedRandom plugin.

3. Use random() or choose() expression. For example:

Set RoomIsDark to choose(0,1)