Help updating from: OS X Yosemite Version 10.10.5, when I click to software update it tells me there is no updates available, due to this I cannot use most functions/apps on my Mac. what Can I do?

On a Mac there is a difference between software updates and software upgrades. To upgrade to OS X 10.11, see information in How to get old versions of macOS - Apple Support

Also see the following:

The model year of a MacBook Pro is available at Apple menu > About This Mac.

An Early 2008 through mid 2009 MacBook Pro can be upgraded to El Capitan 10.11.6 but no later version. See: How to get old versions of macOS - Apple Support

A mid 2010 through late 2011 MacBook Pro can be upgraded to High Sierra 10.13.6 but no later version. See: How to get old versions of macOS - Apple Support

A mid 2012 through early 2013 MacBook Pro can be upgraded to Catalina 10.15.7 but no later. See: How to get old versions of macOS - Apple Support

A late 2013 and mid 2014 can be upgraded to the latest  version of Big Sur macOS 11 but no later. See: How to get old versions of macOS - Apple Support

An early 2015 or later can be upgraded to the current version of Monterey macOS 12. See: How to upgrade to macOS Monterey - Apple Support