Isometric movements are always harder because you rarely walk, run or jump on one leg.
Any exercise involving 1 leg removes the mental roadmap of stabilizing muscles your body as acquired over its lifetime. Isometric exercises are fantastic for strength and balance by removing the overcompensation that's been created by your dominant side (everyone has a stronger side).
Using a chair or a bench (or purchasing a plyometric platform) is great for balancing our your muscles and building your stabilizing muscles. You can hold a dumbell or kettlebell while simply stepping up.
Using a kettlebell or two kettlebells are great for practicing squats and building your balancing/stabilizing muscles.
This is kind of off topic but useful info for your progression and best part is you can do Bulgarian split squats at home, and I've found Greg really know's his stuff:
https://youtube.com/shorts/talu7p2UZ...eAo3PdcAOaSje2
Highly recommend doing stuff at home in addition to seeing your trainer. You'll want to learn what feels right and what works on your own as well as working with your trainer. So that you learn to trust yourself not just him. That way you don't become too dependent on him and you can always ask questions here of course.
The most important thing is giving this time - spend the next year slowly building up the weight and learning what exercises you feel results from and focus on those. The mind muscle connection you are looking for can take as much as 3 months to begin to begin to crystalize.