I’ve been enjoying my use of LibreOffice. It’s a great office suite of applications for many uses. The Document Foundation provides a migration document too for those with complex inventories of documents. There’s information in that document about a neat feature of interoperability with LibreOffice: “MS Office is able to read and write ODF format since version 2007, although with several important exceptions, especially in the case of spreadsheets, up to version 2013, which is supporting the reference implementation of ODF 1.2. Also, if the other party does not have LibreOffice and only needs to read or print the document, this can be exchanged in PDF format, either read-only for the final versions, or the Hybrid PDF that can be further edited in LibreOffice without loss of formatting or information.”
They also gratefully accept donations.
Use LibreOffice. It’s a great value. Most people will save more than the cost of their hardware using it if they use LibreOffice instead of the “pro” licences from M$. It has all the most-used features of office suites and few of its own that maximizes the value of your hardware.