title: How to write a field to change an existing html (or php) file?
body: <p>apologies if this seems like a silly question. I'm very new to coding in general and have little to know knowledge of how write what I'm trying to put together.</p>
  
  <p>I just set up a very simple admin page for my site using php and a mySQL database. I'd like to be able to make some basic fields in the admin page to adjust small details in the sidebar of my site. I currently have my sidebar in a seperate php file, so in order for the change to be site-wide all I would have to do is edit "sidebar.php". What do you think would be the best way to tackle this? My goal is to keep this as simple as possible.</p>
  
  <p>Thanks!</p>