• Official Guide
• VMagnin's post
• NOTE: Make sure to do sudo apt update after adding intel's repositories to apt.
• VMagnin's post regarding sourcing /opt/intel/oneapi/setvars.sh
• Another useful source

My route:

1. curl -Lo- https://apt.repos.intel.com/intel-gpg-keys/GPG-PUB-KEY-INTEL-SW-PRODUCTS.PUB | sudo gpg --dearmor -o /usr/share/keyrings/oneapi-archive-keyring.gpg
2. sudo tee /etc/apt/sources.list.d/oneAPI.list <<< "deb [signed-by=/usr/share/keyrings/oneapi-archive-keyring.gpg] https://apt.repos.intel.com/oneapi all main"
3. sudo apt update