A family of Microsoft word processing software products for creating web, email, and print documents.
Came here with the same problem on a lenovo chromebook, word app not playing nicely with the trackpad. Tried many things and then starting guessing....partial solution discovered:
Put your cursor at the starting point of your selection, hold shift and click and drag across the area you want to select.
It doesn't highlight as you go, but when you release it does correctly then highlight the area you have selected (for cutting etc.)
Hope this helps,
Lenovo C340-15 for reference, using word on a 365 subscription.