I recommend these easy first steps to for an average user:

1. Install @signalappSignal, and *delete* WhatsApp
2. Start using or @librewolf with the @ublockorigin extension
3. Start using @libreoffice for documents and spreadsheets
4. Use a free opensource email client e.g. @thunderbirdThunderbird: Free Your Inbox

All of the above can be done on non free operating systems.

Start experimenting with on a spare computer or laptop. All recommended software works there as well.

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