Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Excel is part of the Office apps. You have to install the entire Office apps. There's no standalone just for Excel.
What kind of license do you have?
I saw you picked Microsoft 365, so I assume you have subscription? If so, you can go ahead and install.
Please go to https://www.office.com
Sign into the Microsoft account you used for the subscription. Click on Apps on the left.
Then on the upper right, click on "Install apps". This will now download the installer file. Once downloaded, click on the file to install. It will install the Desktop version of the apps for you then.