How to insert new video segment into a clip & retain audio of the original

I want to edit in some new video only [without audio] cut away shots into an existing clip but retain all the audio of the original clip that is receiving the insert.

I’m told womble mpeg wizard whch I have can do this, but I can’t figure out how?

Does anyone have a step by step guide or suggest another software with guide. [nothing too complicated please]

Have I posted this in the wrong forum?

I love using Womble. It comes with a comprehensive guide. At the top of the window, click on help and go to what you need to do.