Is my page size causing 100% cpu usage

Yes, you can have a text box that scrolls (just select "Show Vertical Scroll Bar" from the properties dialog box for the text box).

However, it's generally bad e-learning design to be "wordy" -- even more so than it would in a print document. I strongly suggest that you try to make your text more concise and, if there's really too much to fit on a normal-sized page without adding a scrolling text box (which I'm generally against, unless it's for "fine print" stuff, like a user-agreement or something like that), then see if you can "chunk" the text into multiple pages. For example, if the introduction covers information about the purpose of the test, instructions for taking the test, consequences of passing or failing the test, etc., then try making each of those categories of introductory information a separate page.

In any event, creating an oversize page that doesn't fit on a user's screen really would not be the best design solution, even if it didn't cause technical problems.