I cannot install WINE

So I asume you followed the instructions on https://wiki.winehq.org/Ubuntu. But since elementary OS is based on Ubuntu 18.04, you should have used the ppa for Ubuntu bionic, not focal.

To try and fix the issue:

1. please remove the focal ppa:
   sudo add-apt-repository --remove 'deb https://dl.winehq.org/wine-builds/ubuntu/ focal main'
sudo apt update

2. follow the istructions from https://linuxize.com/post/how-to-install-wine-on-ubuntu-18-04/#installing-wine-50-on-ubuntu to install wine.

EDIT:

Since the instructions in the link at step 2 might be unavailable in the future, I'll paste them below (only of distributions based on Ubuntu 18.04):

Enable the 32-bit architecture and update the packages list:

sudo dpkg --add-architecture i386  
sudo apt update 

Import the WineHQ repository’s GPG key using the following wget command:

wget -qO- https://dl.winehq.org/wine-builds/winehq.key | sudo apt-key add -  

Add the WineHQ repository to your system:

sudo apt install software-properties-common  
sudo apt-add-repository 'deb http://dl.winehq.org/wine-builds/ubuntu/ bionic main'  

Install FAudio from the OBS repository:

wget -qO- https://download.opensuse.org/repositories/Emulators:/Wine:/Debian/xUbuntu_18.04/Release.key | sudo apt-key add -  
sudo sh -c 'echo "deb https://download.opensuse.org/repositories/Emulators:/Wine:/Debian/xUbuntu_18.04/ ./" > /etc/apt/sources.list.d/obs.list'  
sudo apt update 

Install Wine 5.0 package by typing:

sudo apt-get install --install-recommends winehq-stable  

Verify the Wine installation:

wine --version  

The output should look something like this:

wine-5.0