Sound on sound question

I have a stereo track and split it. I now want to place the left track onto the right track to make a mono recording.
How do I add sounds to sounds?

Thank you.

Leave it unsplit.

Tracks > Stereo Track to Mono.


Tried that too. After exporting, it’s still in stereo.
How do I get it into mono?

Hold it. Thanks, I figured it out.