How can I move mykeyboard?

If the keyboard is split and covering your text, Pull the two ends of the keyboard together - into the middle of the screen. You can also tap and hold down on the little keyboard icon in the lower right corner of the keyboard and select - Dock and Merge.

If the keyboard is up on the middle of the screen, but not split, and you want to move it back to the bottom - tap and hold down on the little keyboard and icon and select - Dock

You can turn the split keyboard off in Settings>General>Keyboard>Split Keyboard>Off.

It probably just happened accidentally. Anyway, I'm glad I was able to help.