I don't know what this people talking about,u need just double click on deb file it will open grahical installer,if not check file assisation it shoulb be assigned to Eddy program.It's pop os alternative to gdebi.
In addition to what other people have said about gdebi, I'm surprised it's not there by default in Pop. I thought it was there in pretty much all Ubuntu-based distros (except where alternatives are used).
I totally get not wanting to use the terminal for this purpose. It's pretty rare that I download and install a .deb, but when I do, it's nice to just click it straight from the browser and not have to navigate to my download folder in the terminal. And given how rarely I download and install .deb files, I have to look up the command every time.
I've tried that but it's hard to follow the install. Like when it installs and I press the green open button, it just doesn't work, and doesn't behave like I would expect it too. E.g. click open it doesn't work, or no desktop icon is created, and it doesn't show up in the app drawer, evening making in into an executable in the properties doesn't work sometimes. (I would expect it to act like an .exe or flatpak.) I'll try to get it working again rn.
Odd. Can you share which application is it that you are trying to install. Maybe it doesn't create a desktop file hence the lack of an launcher in the app drawer¿?
Unless your program doesnt have a flatpak or appimage just avoid deb as sometimes they are behind flatpak. I noticed this in the discover store for kde plasma for example. Plus flatpaks and appimages are the future as they support all distributions instead of mainly just debian-based ones.