Before you proceed, you need Spaces installed on your phone.
How to delete a Space?
Step 1 - Open the Space which you want to delete and click on the three-lined menu icon located on the top right corner of the screen.
Step 2 - SelectSettings.
Step 3 - Navigate to the end, click on Delete Space. It would open a confirmation screen "Are you sure you want to Delete this space?" > Click on Delete and you are done.
You are done!