The following have been tested on MSI Katana GF66 with i5-11400H/RTX3050 and i5-12400H/RTX3050, and MSI Aegis i7-11700K/RTX3070
Step 1: Download the image for Ubuntu 20.04.6 (ubuntu-20.04.6-desktop-amd64.iso) and create a bootable USB following the official instruction (for Mac, for Windows, for Ubuntu).
Step 1.5: (For dual boot only). Boot into windows, then use disk management → shrink volumes (you may run into the error “The Volume You Have Selected to Shrink May Be Corrupted”, to resolve it, right click on the disk → properties → Tools → Check → Scan Drive → Repair Drive → Repair now).
Step 2: Insert the bootable USB drive to the new computer. Power on the computer. If you’re using a MSI computer, press and hold the Del key to enter the BIOS manu. Set boot priority such that the computer boots from the inserted USB drive. Disable the Secure Boot support (this help avoid complications when installing GPU drivers).
Step 3: Follow the instructions to finish installing Ubuntu. Make sure you check “Install third-party software …”. If the computer has both a SSD and a mechanical drive, make sure install to the SSD.
Step 4: After Ubuntu is successfully installed, you will still boot into windows by default. To fix this, press the Delete key on booting to enter the BIOS menu, then Boot → UEFI Hard Disk Drive BBS Priorities and make Ubuntu the first option.
Step 5: If the computer has a Nvidia GPU, the GPU driver should already be installed. To check, run
nvidia-smi