MacBook pro 17 inch
Need to update os from 10.12.6 to the most recent.
It doesn't show any updates available.
Please help I've tried everything I can think of including restarting.
Thank you
Refer to Update macOS on Mac - Apple Support:
"If Software Update says that your Mac is up to date, then no new software is currently available for your Mac model. Software Update shows only updates and upgrades that are compatible with your Mac."
What specific model 17 inch MacBook Pro is yours? To find out, read Identify your MacBook Pro model - Apple Support. To determine its currently installed operating system version, read Find out which macOS your Mac is using - Apple Support.
There are no MacBook Pro models that are limited to OS X 10.12.6. If that is in fact its currently installed operating system, update it to OS X 10.13.6, here: How to download macOS - Apple Support. Scroll down to High Sierra 10.13.