Before going to the Print dialog, zoom into the area you want to print.
Then press Ctrl+P and under More Options select Current View.
I want to print the entire document; not a particular part of a document.
I don't want to shrink the document as I need the actual size and thus a part of the right side of the document gets cut off.
Your printer cannot print to the edge of the sheet of paper.
In the preview window, the gray area is the area of your printer that cannot be printed to, and these areas are unique to different printers. As a rule, laser printers have a quarter inch unprintable area all four sides and ink jets (perhaps older less expensive ink jets) can have as much as one inch at the bottom which cannot be printed to.
You would need a printer which supports boarderless printing, or print the document to a larger size sheet (tabloid) and trim to the proper margins.