I am kind of new to coding & i’m not sure if there is a feature where I can lock parts of code to avoid fat-fingering or any inadvertent change that may effect the code. Like I could add to the locked code (at the end or something). If there is already something like this where is it?
don’t know what you mean by locking parts of the code.
What you can do is, maybe, folding (depends on which language you use) or hiding (view menu) the parts which shouldn’t be edited anymore.
You need to be using a versioning system instead such as Git or Mercurial. It requires some learning but it is time well spent.