there are a number of "no cost" applications that will read/write MS Office files.
most come with caveats "some features may not be supported"
for simple stuff, not an issue.
but you cannot control stuff other people send you which may have "features . . . ."
check eBay/et al for "outdated versions" - the most "reliable" buys are those with a CD (vs. keys to "downloaded . . .")
prices are in the $50 range. and Office 16+ (and maybe earlier...) provide free updates to read / write the 'docx' 'xlsx' MS formats.
it's one of those "safer bets" in dealing with MicroSoft . . .
me, two kids and one cousin did the 'outdated' approach and haven't had issues.
yes . . . I have three kids. one is a Mac-head. currently making bundles on VR reality games for Google . . .
there is life beyond MicroSoft . . . .