Adding sound to an existing MPEG video file

Apologies if this is self evident within the program - unfortunately you are dealing with someone who is fast approaching his 90’s.

I have a video created with Roxio Easy VHS to DVD 3. The video does not have sound and I am at a loss how to add sound.

I have had several attempts to do this but when I try to put a converted file on the Roxio Easy VHS to DVD 3 program for editing the Roxio program will not accept the converted Video file.

I would really appreciate any advice on what I should do to add a musical background that would be acceptable to a video created with Roxio Easy VHS to DVD 3.

Apologies once again for what may be a simple solution.

Kind Regards

Open Shotcut video editor.
Drag and drop your converted video into the playlist then drag it to the timeline.
Drag and drop your audio track into the playlist.
Create a new audio track in the timeline (Ctrl+U), drag your imported audio to the new track.

(I’ve added a still image, but the process is identical)
Also I advise to check the Shotcut video tutorials on YouTube, there are many.

Thank you so much for your help it is deeply appreciated.
I followed everything you suggested but I confess to being very cautious.
Would you please tell me how to save this project so that I finish up with a file that is usable in my Roxio Easy VHS To DVD program.
Once again - thank you