Why can't I upgrade my MacBook Pro to Big Sur?

Hello,

Is your MacBook Pro model not listed in this article? macOS Big Sur is compatible with these computers - Apple Support

If so, the simple answer would be the hardware inside of the MacBook Pro. We are living in an age of unprecedented technological innovation. As new technology emerges some older hardware cannot support it, leading to the unavailability of software upgrades. This would indicate that you may want to start researching a newer device to purchase.

Depending on which macOS version you are currently using you may have an older version available that's newer than your current one.

How to get old versions of macOS - Apple Support

If you MacBook Pro model is listed as compatible, for macOS Big Sur, but cannot upgrade, this article would be helpful to find out why and how to upgrade.

If an error occurred while updating or installing macOS - Apple Support

I hope this helps.

If you think it should be qualified, post your MacBook Pro model-year and current MacOS version.