Increasing core strength & conditioning can make a massive difference to technical riding (and life in general), especially if you are a desk jockey rather than a manual worker.
It is one of those things that you are told, forget/ignore and then, many years later, when you do finally get around to working on your core strength, you think,
“Why, oh why didn’t I do this years ago????”
Start off with simple bodyweight exercises a couple of times per week. variations on Pressups, planks, pullups, squats, lunges, skipping and the like rather than focussing on “abs” exercises like crunches.
Vary your riding, with hard efforts, and become comfortable/relaxed on technical terrain -good core strength will assist with this.
ps. Do try to avoid over-training. I fell into this trap earlier this year and felt tired a lot. Get a lot of sleep.