How do I switch between keyboard on screen and my keyboard?

There will be a special key to press somewhere near the left bottom of screen keyboard . It will look like ABC123 and switches the keyboard to special characters and numbers .

I assume you mean the Nook keyboard doesn't allow switching between numbers and letters. The built in Nook keyboard isn't the smartest or only keyboard app out there. Now that it's totally free strongly recommend you go into the Google Play Store and install SwiftKey. One hour using it and you'll wonder why you ever put up with Barnes and Nobles chunky idea of a keyboard. Even Google itself has their own keyboard app. You can have multiple keyboard apps installed at the same time. Just use the Switch Keyboard option to toggle between then.
As far as SwiftKey is concerned one of the main features that first sold me on it is it can be resized. I always hated the Nook keyboard just took up so much of your available screen space leaving so little for the input area. Did you know SwiftKey can be setup to show a numbers row at the top just like a regular PC keyboard? Also it can learn your typing patterns over time and predict the most likely word you will use next. Just click the word in the predictions bar.

About the only solution that might help is 'contact cleaner' available at electronic stores such as Radio Shack.
Use very sparingly into the switch opening and operate it multiple times to 'wipe' the contacts.
Avoid getting the spray on some plastics but if this solves the problem, the solution will also leave a protective coating behind on the contact surfaces.

Good luck-

Your on screen keyboard should have a button labeled ?123, after pressing this to switch to numbers/symbols, press the Shift key to change to additional symbols.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/daniel_e90a831f4dd5fc5d

Go to Settings, Input and you should see options for turning off voice input, and also for selecting a keyboard (if more than one option is included).

Heres a few ways to get around issues with keyboading.
What keyboard app are you using? You can download alternative keyboard apps as one way to get around bugs in the stock Nook Keyboard app. I love Swiftkey as it's now free. Google itself has has its own keyboard app. Both run circles around stock aspecially Swiftkey.

Are you using any of the accessibility features? Go Settings - Accessibility. Make sure the choices are all set to off.

Press the Switch Keyboard button. Press Set up input methods.
Be sure it shows your correct language, turn Auto capitalization to off. Turn auto correction to off.

Triple check your screen is really really clean and smooth to the touch.

Go into system to Language and input.
Click on the UNTICKED Google Keyboard English-box at right of page.
If its like my mark 1 Hudl or my wifes Hudl it then shows a Language screen.
Go back and double click the above and go down to text correction where you can either switch off or adjust the sensitivity of the predictions.
Once you have done this a single screen click shows you this "missing"screen.
If you totally dislike the Google keyboard then go into language screen and choose Qwerty keyboard.

There's an on screen keyboard available! XP: http://www.microsoft.com/windowsxp/using/accessibility/oskturnonuse.mspx Vista: http://www.microsoft.com/enable/training/windowsvista/osk.aspx The Windows 7 Flavor is available through the Ease of Access Panel just like Vista. This might help out a bit.

Disable screen rotation.

i have the same problem.
I run the windows screen keyboard and i discovered that when i press both r+t keys and u+y both shifts are switching on. i'm not able to switch it off even using mouse on screen keyboard.
as temporary workaround i press fn key then i press shift on screen keyboard, then both shifts switches off.
i didn't fount full solution.