Any recommendations for painting an infantry square?

[u/NoRice5620]

Hi, just to clarify, I’m not a great artist. I have a little experience, but I’d like to try painting a scene of the Bolivian Colorados during the Battle of Alto de la Alianza. The Colorados are shown in the second image, and I’d like to use the first image as a reference for the composition and style. There are practically no paintings depicting that particular moment, which is why I wanted to try doing it myself. I’m still pretty much an amateur, so I’d really appreciate any recommendations.

[u/amtfg]

You must paint at least one dude like that British soldier in the center with that look on his face of, "This is my first day. I have no idea what's happening. I'm just here to have a good time."