Colors? Values? Loose?

I am really excited to paint in the style of Andrew Pitt. A painter I just discovered on YouTube. Check out his videos: https://www.youtube.com/c/AndrewPittArtist/videos

He is, in my opinion another great English artist.

With the painting below, I found it quite easy to "lift" the whites of the tree trunks off of the paper. It's a very muddy painting, and I don't really care for it; but I see promise in it.

The Odd Couple, Robert Hopkins - 2021, on Saunders Watercolor (11x14)