Thingiverse is one of the most popular online communities for 3D printing enthusiasts. Here are some of the best places to find 3D printer G-Code files: I wrote an article about How to Modify G-Code in Cura which can be useful in these situations. That means that you may need to edit your G-Code to get it printed properly on your setup. Just be aware that G-Codes are tweaked to specific setups depending on the filament and bed type, as stated by one user.
There are several ways to find 3D printer G-Code files online, including searching popular 3D printing websites, browsing through online forums, and using search engines. Where Do You Find 3D Printer G-Code Files?