Losing weight and losing fat don't always amount to the same thing.
OP, it sounds like you want to change your body composition rather than get smaller.
The answer is very similar though, it's 80 % diet and 20 % exercise. I would suggest lean protein at every meal, veg, some fruit and good quality starchy carbs (grains, rice, potatoes, pasta) after training, some good quality fats (nuts, salmon, etc). And as little alcohol as possible.
Focus on strength training, with a bit of cardio afterwards (it doesn't have to be anything crazy, long walks can really do wonders!)
If you want to get into the details a bit more, there are science-based programs you can follow, like Renaissance Periodization (there are others but I have personal experience of this one and can vouch for it)
The main thing to remember though, OP is that changing your body composition can take time, and requires consistency. Don't be discouraged if you don't see results straight away, it is a marathon rather than a race, but if you stick with it you will get there!