Numbers

to select a cell, single click the cell

to select a range of cells use one of the following:

• click and hold on the top left cell, then drag to the bottom right cell (take the actions at about the same pace as you can speak "click hold drag")
• single click the top left, then hold the <shift> key, single click the bottom right

if you want to move the content of a cell (or range of cells). select the range, then pause, then click and hold. wait until the range "pops" out fo the table, then drag

What are you trying to do? I cannot really help because I do not have a windows machine to try anything on. Can you share the document so I can at least try from my computer?

If not can you create a similar without any sensitive information that exhibits the same behavior?

are you using Numbers via a web browser on iCloud?