Dear new developer,
I don’t know how old you are. All I can tell you is that you should take care of your body. This includes tasks that all folks should do (get good sleep, exercise, get the regular checkups for body, eyes, teeth, skin) as well as some tasks specific to desk jockeys (get up, maybe get a standing desk, look away from the computer once in a while) and some tasks specific to being a software engineer (get an ergonomic keyboard).
Whatever you do, listen to your body. Take regular breaks. Buy the equipment you need. When I was young, my body seemed to be an endless resource.
It is not.
Sincerely,
Dan