Im not able to give any advice but I want to follow this as I am getting gastric bypass done this June.

I train clients that had gastric bypass. It depends on where in your exercise recovery you are, any specific limitations you may have and It also depends on how much exercise you did before the surgery. So, not knowing your background I couldn’t tell you a specific plan, But I can say combining some cardio with lightweight strength training will help Your strength and endurance. Also, Nutrition is key!