I am brand new to printing with my own stuff, I have a few questions. for background I have an ender 3 pro 1. What programs are you using to design? any recommendations and I have a bit of a budget for it 2. what filaments can I use? and how do I know what to use for the print? 3. what are the mods I can make for the printer for quality of life?  I have done a handful of little prints that I found on here and know the printer works awesome! Any advice is greatly appreciated