I have macOS high sierra version 10.13.6 can this be upgraded?

Perhaps if you should use the following article instructions and identify

your device build model year? That can help upgrade your Mac to latest

supported macOS version; as there are downloadable installers* you use.

How to download and install macOS - Apple Support*

//support.apple.com/en-us/HT211683

macOS Compatibility Guide by Mac Model

https://eshop.macsales.com/guides/Mac_OS_X_Compatibility

Upgrade paths available to Intel Macs - Apple Community

//discussions.apple.com/docs/DOC-13695

*These are DIY downloadable installers; with details from this page, you

can upgrade your Mac operating system, or renew an existing old one.

Download and install current or previous versions of the

Mac operating system on compatible Mac computers.

Use Safari browser in your Mac to download & install supported macOS.

Upgrade Paths for Macs running Intel & and Apple Silicon CPUs

https://www.macmaps.com/docs/DOC-13695/

[..There also are tools in your Mac to repair and reinstall a macOS..]

The family of MacBook Pro models offer examples of most

build versions; 2008 to Recent ones, with identifiers, too.

Identify your Mac Book Pro model - Apple Support

//support.apple.com/en-us/HT201300

What is your MacBook model? The early 2010 eras and late 2009 cannot update further then high Sierra