Will exercising as a mountaineer lead to muscle loss?

I am considering taking Maunza to lose weight, but I am worried that if I reduce my food intake, I might lose muscle as well as fat very quickly.

I'm wondering if it will be physically okay to combine cardio and strength training at the gym as usual.

Since I am losing fat and my body fat is decreasing, I have weak muscles, so I am wondering if I might experience muscle loss again due to my own efforts even if I exercise. Is it possible to minimize muscle loss?