After bringing up the palette, click on the square root symbol. A radical symbol with a square box appears on your notebook command line. Click on the square box within the Radical and enter 5. Move cursor to right of that symbol and left click again. Then add two forward slashes and an N. Execute command. I copied that operation out of my notebook to place in this message. When I paste results from the copy, rather than showing the square root Radical sign, Sqrt[5] is displayed. In the notebook a 5 is shown within the square root Radical sign.
In[1]:= Sqrt[5] // N
Out[1]= 2.23607