I have a macbook with OS 10.6.8 can I upgrade the OS system?

El Capitan 10.11 Compatibility information

macOS Sierra 10.12: Compatible Apps

Also check to make sure there is a compatible driver for your printer.

Do a backup before installing, preferable 2 backups on 2 different drives.

Back up your data, check your applications for compatibility, and download El Capitan from the Mac App Store.

(161109)

MacBook Mid 2010 models can be upgraded to 16 GBs of RAM. You should consider upgrading to at least 8 GBs.

Also, upgrading your lethargic 5400 rpm HD to a SSD will make the biggest performance difference.

If it is truly a MacBook Mid 2010 model, it will run High Sierra. But, you'll need to upgrade to El Capitan first.

Just saying it will be quite slow and get quite hot

Just saying it will be quite slow and get quite hot

Have never really found that to be the case. All of the macOS upgrades have always performed on par with the previous macOS versions.