Loop Tools Add-on

This post is in response to a question on the sci-fi box gallery project by kksbum99 .

To enable the loop tools add-on, 1, go to Edit>Preferences, then select the Add-on tab,

2, search 'loop tools', and 3, enable the add-on.

4, you should see the edit tab in the right panel when in edit mode.

5, this will give you some options, including circle.

Here is a demo of what you can do.

And the result with a few select bevel edges, subsurf, and shade smooth.