I installed Fedora Cinnamon, and after the installation was complete, I updated it as usual with sudo dnf update. After the update, when I restarted, I was able to log in and enter my password. After successfully logging in, the screen went black, with only the mouse visible. So I reinstalled it and asked the AI, and it said I must use RPM Fusion. I followed the instructions to install it, but it’s still the same. Please enlighten me, because I’m interested in Fedora. 
My laptop is an Acer Swift 3 Infinity 4, Intel i5, Intel Iris XE graphics. Thank you.
First rule on the road to enlightenment: put away the AI.
As a workaround for your problem while it is fixed,
go to a new tty with
ctrl+alt+f3
and log in there.
To start Cinnamon manually type
cinnamon-session
I have not confirmed this, as I don’t have Cinnamon, so if that cinnamon-session does not work then have a search and you will find the correct command eventually.
thank you sir
Glad to help, did it work?