How to manage both health and continuous learning being a hardcore software engineer

I was fit during my college days, but after starting my job, my health started deteriorating day by day, I gained almost 20 kg since I started my job. Recently I started going to gym and I lost 7 kg and I'm still going to gym now. Now the problem is when I try to learn/study on daily basis, I don't have much time to go to gym and vice-versa. I am a hardcore engineer and I love to read or gain knowledge about internal working of any technology but now I also want to be fit and disease free, can you suggest me how to balance both of these while also keeping some personal time off as well? Note - I'm working in a startup as a platform engineer so I have to work a bit longer (8-10 hrs) a day most of the days.