You need to add photos of other walls. Also, make a quick scaled drawing of room - include dimensions for walls/windows/doorway(s)/etc. This will help other users to make suggestions/offer advice.

You still can make built-ins work. Since we do not know your style, here is modern farmhouse bedroom.

I would paint built-ins the same color as walls.

Cottage bedroom with minimalist accents

As for bedding, stick with crisp white base layers and add color/pattern with pillows or a textured throw.

Consider neutral or earth-toned pillows (swap red for soft greens, warm golds, or terracotta).

Drape a linen or woven throw at the end to add texture.

Is that the only wall the bed can be against? What is on the other walls? What is the size of the room?