Dear Thien Nguyen1,
Good day! Thank you for posting to Microsoft Community. We are happy to help you.
As per your description, please don’t worry, we can work together to narrow down and resolve the situation.
In Word 365, you may use mouse to select multiple non-contiguous cells in a Word table. To select multiple non-contiguous rows, move the cursor to the left of the first row until it changes into a white right arrow and then click to select the row. Press Ctrl and click with the white right arrow on subsequent rows.

Your understanding and patience will be highly appreciated. I hope that you are keeping safe and well!
Sincerely,
Waqas Muhammad
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