Audio file recorded only with L channel, want it to be even

I have a file that I’m adding as a track, which only has audio in the L channel. (I used a Zoom H4 in multitrack mode and I only had 1 mic, so the file was saved as only having audio in the L channel.)
I’m editing it now, and I want to have the same sounds in the L channel coming out of the R channel.
What do I do? I tried using “normalize both channels independently”, but that just made the whole audio track into very loud static.
Is there a way to do this?

Split the track into two mono tracks, then delete the track that does not have the recording. Mono tracks will play through both left and right.
See here for how to split the track to mono: