[2019] What i do wrong with bedroom?

Bedrooms are automatically occupied by settlers that are a family. Sounds like only two of your settlers for that one room are a family. The other three settlers will need their own rooms if they are all single. You can also manually assign settlers to rooms if you want them all to share one. This is done through the room edit window. Though, they won't really like this after a time.

As for the uniforms, I'm not really sure why they wouldn't equip anything. Did you properly assign the uniforms to their professions? They'll only go get items if they match the profession tied to the uniform.

When you have the room menu open, there's the room overlay on the right. You can add/remove settlers manually by opening the room edit button beside the 'A' button.

Items are spawning on the roof because you need more space in that room. Try building some containers to put items in.