what needs to be done to make excell work on my computer?

mikerzep wrote:

what needs to be done to make excell work on my computer?

Assuming much, including a recent upgrade to macOS 10.15… You probably had Office 2011 or earlier installed, and that’s incompatible with macOS 10.15 and later. You will need to acquire Office 2016, Office 2019, Office 2021 (current), or an Office 365 subscription, or migrate to LibreOffice (free), and Apple iWork Pages, Numbers, and Keynote (all free) can read and write many Office documents

Well without knowing what computer (including model year and version of Mac OS is currently installed) we cannot possibly answer your question. Also, if you already have Excel (note correct spelling) we need to know the version you own, please remember Excel has been in the market well over 25 years in many different versions and for multiple platforms.

With a question as vague as that all I can suggest is make you sure you have a version right for the version of the OS you have.