Where do I find Software updates

Are we mixing software update with software upGrade.

High Sierra has not had an update since September 2020 and doubtful it will see any more updates. Remember, an update is within the Same version of macOS

If what is really meant is upGrade - ah that is different. This Link will take you to an Apple Site where newer versions of macOS can be found. Now, it will be up to you to determine the Age Of the computer and thus what version of macOS it qualifies for.

Very Important - The links in next page to start the download of whatever version of macOS Must be opened Only in Safari as FF / Chrome will not work. Also, do a Time Machine Backup Before attempting any upGrade

Hi, if you are using a Mac then try this https://support.apple.com/en-us/HT201541

If not then please tell me what device you are trying to update.