The Prt Screen key is to the right of the F12 key and although the word is on the top, you should not use the shift key.
According to acer web pages
You don't need the the Control key to do the whole screen as other answer indicates.
However to screen shot a window, you need to do alt and the key.
=== Generically in MS Related Programs and others while in Windows
Alt+prt screen keys(together) captures a window on your screen (for example just your browser or a game window) (the window the cursor is currently in )
(Control) Ctrl+prt screen (together) captures you whole screen (including the toolbar)
Then, Ctrl+V will paste the capture into any window program accepting the capture. (Paint, Word, excel, etc. )
For Games in Xbox related games they added an extra way in Windows 10,
It is not a part of Windows 7 . I double checked.
Steam also has added its own way too.
Indicate if you need the extra information and I can look it up.