I've got an Ender 3 3D printer. I use Cura to slice my files and prepare them for printing—these are the profiles I use.
This profile is exactly the same as the profile provided by the creator of the 36" Northern Pike RC Airplane, but updated for modern Cura versions. You will probably need to fine-tune retraction settings for your printer.
This is my version of the above PETG thin-wall profile. I'm working on printing the 36" Northern Pike RC Airplane for a friend. I'm using eSun PETG filament, so this profile is especially for PETG parts. It mostly has modifications with the retraction settings.
Check out this huge list of Ender 3 parts, upgrades, and tips I've compiled! It should be immensly useful to anyone who's just starting with an Ender 3 printer.