He's referring to the Shadows/ Highlights tool in PS. It'll help lighten the shadows and darken hot spots. The main issue in this photo is the angle of light; you can deal with it to a certain extent in post-processing, but if you can it's always best to deal with it in the field (in this case moving to the right).
Just to polish-up your image for presentation there is also some darker OOF stuff at bottom and right that you could easily take care of (by cloning or QM, for example).
Great job of critiquing by all above so nothing to add other than toning down the blue sky a bit. Thanks to all above. And welcome to Ken. It's great to see so many new folks posting here today.
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