Open GIMP, and open the Preferences dialog. The locations will depend on your OS, but you can always find them the same way. Luckily, there are other font folders you can use to install your fonts to use in GIMP. There are a few situations where it’s not possible to edit the default system folders, such as on a public or shared computer. When you install your fonts there, they can be accessed by all the programs on your computer, which usually makes things a whole lot easier. Most of the time, it’s better to use your operating system’s default fonts folder. If you’re not sure where to get new fonts, I’ve put together a few of the best options below. To install them for everyone, copy your OpenType OTF files into /usr/share/fonts/opentype/ and TrueType TTF files into the /usr/share/fonts/truetype/ folder. To install for your own account, simply create a new folder named “.fonts” in your home directory and copy all your font files there. These instructions may vary a bit depending on which flavor of Linux you’re running, but covering all the variations would probably be an entire article all by itself!
Linux users are probably used to a bit of hardship during any setup process, but they also get a relatively easy ride here.
Even though it shows less info, the macOS font preview still manages to look much nicer