Cool. I can do that. The next question

[winged sluice]

There are several ways. Maybe you block the way with something.. maybe a door you need to find a key for to open it. You can guide them with something interesting in the room, a brighter light or something making noise in the room.. add some loot (if you have loot) thats visible for the player when peaking into the room.
Or just add some signs that explains whats in that room to make the player curious what that sign means 😄

If the player is low on ammo or health, they will explore every room on their own, i guess, to find stuff to survive-

[ruby granite]

Don't judge my artistry!!

but I was thinking to get into the appartments to have the player go through the construction zone to get into the alleway to get in from behind as a first "challenge"

but ya

Not really good at these things XD

[ruby granite]

This is true. I did not thing about this/

[winged sluice]

Have you played Fallout, Metro or Bioshock?

[ruby granite]

Best games !

[winged sluice]

Then think about how they did it.

The player want to find stuff they (may never) need, and love to gather the stuff.

[ruby granite]

Cool. Let me re-draw the map with a focus on just the appartments

where doors will be locked and stuff like that

[winged sluice]

If you provide interesting loot or something to explore in some rooms, they will automatically discover every room

[ruby granite]

Thanks a bunch!! Let me give this a shot!