You can get a printer for $150. I have a very reliable Ender 3 pro. After that is the filament @ about $20/1kg roll. Start with plain PLA filament. I like Sunlu, but have a couple other brands.

You need a slicer program to turn .stl files into gcode. Cura is what I use. https://ultimaker.com/software/ultimaker-cura
You will be working with metric measurements. Cura has several config profiles to produce fine or rough results. Start with the Standard Quality config and adjust temps to 215ºC and 60ºC