Well I'm affraid I am going to say watch tutorials

It's hard to teach someone what has to be learned by practice. I can tell you how to use unwrapping methods, I can show you how to unwrap specifically a room for such but you have to practice it. Watch tutorials on how models are unwrapped and take that in practice. Try to find out why and how you can best unwrap a specific model.
But I can summit how I would approach this:
- 1 tileable wall texture
- 1 tileable floor texture
- 1 texture for every prop (bed, cubbert etc.)
So when you see this you should just plane unwrap the floor and wall. That you could figure out. For the props you should unwrap everything and lay the uv's out uniquely. Maybe some parts could overlap eachother but that you would all have to figure out by practicing it.
Hope it gives you a wider perspective on your learning proces

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