upgrading to Venture

Use the App Store

To download macOS from the App Store, you must download from a Mac that is compatible with that macOS. If your Mac isn't compatible, the App Store dims the Get button, says that the macOS is not compatible with this device, or says that the requested version of macOS is not available.

How to download and install macOS - Apple Support

Choose Ventura or Sonoma

This Mac Studio Qualifies for Both

Add on

Suggest having at least 50 GB of Empty Space on the drive.

It will allow the Full Version ( about 12.xx GB ) to download, then expand and then commence to install.

If there is Third Party Security Software installed - remove it.

It will interfere with both the download and installation process

Always make a Time Machine Backup  before doing any upDates / upGrades