If there are rocks here, how have you modified your current workouts?

I’ve been doing more bouldering (in a gym) lately and I’ve noticed that (I think) I’m not progressing due to upper body strength weakness. I looked at the different exercises I could do and came across this article: https://www.rei.com/learn/expert-advice/rock-climbing-how-to-cross-train.html They look good, but to give me some background I don’t really have anyone more experienced …