Yes, you can always make changes to the set up inside your base camp.

To relocate the buildings, hold and drop the building to the destinated positions. When you pick up a building, green boxes will appear to indicate the area that the building would take up. The relocation will fail If the building overlaps with other existing objects.

You can also add/remove decors inside your camp.

Steps to add decors:

1/ Tap   on the left side of the game.

2/ Select the [Decor] tag.

3/ Choose the item and drop it into your base.

Steps to remove decors:

1/ Select a decor.

2/ Tap 

3/ Tap [Confirm].

*100% of the decor’s cost will be refunded when it is demolished.