new to photoshop. how do i get to see contents (capacity) of scratch disk and how do i change ?

how do i format this message i.e. font size color ?

Hargold, welcome to RetouchPRO! Your scratch disk is just a place that Photoshop uses as a temporary working area to store interim files it is working on. If you have a large image with many layers at high resolution, Photoshop will often not have enough RAM to keep everything in active memory, so it needs a scratch pad area. When you close Photoshop down normally, it clears the scratch disk files.
Unless you designate a Scratch Disk in the preferences when you install Photoshop, your system drive (C) will be the default scratch disk. If you have a 2nd physical drive in your computer, Photoshop will run more efficiently if the other drive is designated as the scratch disk. The only time you will ever notice that there is real usage of the scratch disk is when Photoshop is shut down abnormally (if Photoshop crashes or the computer freezes while Photoshop is active). Then you may find a file with the extension .pst. The file will be very large (usually several hundered MB and you will not be able to open it. You can just trash it.
Regards, Murray