OK you got a good start understanding snap and flatpak thing/sh.t with their problem... (I know some don't agree with me about flatpak 
)
You forgot or miss appImage (another way to have your application), which is "multidistro" (once downloaded, just a right click on it > Properties > a window opens go to the tab "Permission > Check the box "Allow executing file as a program" and you're done, double click to start it)
In all case welcome to Linux and freedom to the way you chose to install your things
Yes there is a way to install via PPA (AKA sudo apt install gimp)
There is a PPA from Panda Jim (than a lot of us are using), you need to instal its repo first > https://launchpad.net/~ubuntuhandbook1/+...buntu/gimp
Roughly in terminal just input
Then you will have the latest GIMP (actually 2.10.34)
For python support in GIMP I would recommend the appimage from Tas_mania (it's really a life saver to not enter in complex install about python 2.7),
it is a GIMP launcher with python support (after you've installed GIMP), here > https://github.com/TasMania17/Gimp-Appim...s/releases (it's an appimage, read above how to make them "active" )
for G'MIC it's here > https://gmic.eu (ZE big plugin but VERY useful for GIMP), maybe I forgot few more important plugin)
And you should be good to go
)You forgot or miss appImage (another way to have your application), which is "multidistro" (once downloaded, just a right click on it > Properties > a window opens go to the tab "Permission > Check the box "Allow executing file as a program" and you're done, double click to start it)
In all case welcome to Linux and freedom to the way you chose to install your things
Yes there is a way to install via PPA (AKA sudo apt install gimp)
There is a PPA from Panda Jim (than a lot of us are using), you need to instal its repo first > https://launchpad.net/~ubuntuhandbook1/+...buntu/gimp
Roughly in terminal just input
Code:
sudo add-apt-repository ppa:ubuntuhandbook1/gimp
sudo apt update
sudo apt install gimpThen you will have the latest GIMP (actually 2.10.34)
For python support in GIMP I would recommend the appimage from Tas_mania (it's really a life saver to not enter in complex install about python 2.7),
it is a GIMP launcher with python support (after you've installed GIMP), here > https://github.com/TasMania17/Gimp-Appim...s/releases (it's an appimage, read above how to make them "active"
)for G'MIC it's here > https://gmic.eu (ZE big plugin but VERY useful for GIMP), maybe I forgot few more important plugin)
And you should be good to go
Patrice