A separate computer may be more affordable than you think. An older desktop or laptop
can be found on Craigslist for 50 to 75 dollars. They might be too slow to run win10 but competent to run linux. Also instead of Ubuntu there is an Ubuntu based distribution called
Zorin Light which runs quickly on older systems. I believe it includes Libre Office; but if it doesn’t you can always add that by using software manager. Finally if you download a Linux distribution from Distrowatch or another site don’t do it on a wireless connection. Plug into your router with an ethernet cable for a more reliable download.
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