Look at the boot screen when you start the computer up - that's the one with the Toshiba logo all over it - and you should see commands like 'Press 'Del' for BIOS' and 'Press 'F8' for boot choices'. There will be one for 'Recovery' if you have a recovery partition. It is sometimes 'F2' but by no means always.
Press whichever is the specified key while the boot screen is showing and the recovery system should start, and once you have made one or two choices via dialogue boxes it will just run until it is completed.
TWO POINTS. The first is that this process will wipe all your own data and applications off the system. I would suggest that you take the hard drive out and slave it to another computer - you may need to use some sort of 'caddy' but they are widely available - to try and save what you can of your own data.
The second is that this process will restore your computer to the condition it was in when it was built ! This means you will have to uninstall any manufacturer installed software that you don't want, and that you will have to re-install all your own appications, and you will have all the updates to do since it was built !
The important bit here, if you decide to go down this route, is to try and back-up your own data - documents, photos, whatever - this is the valuable stuff. You say a 'low-level format has been carried out'. This may mean that your data is already gone, but see if you can still save any of it.