Private Software Recommendations (2025 Update)
Web Browser
TL;DR - use ungoogled-chromium (Chrome without Google) or LibreWolf (Firefox without Mozilla).
Unfortunately, most browsers kind of suck and getting a decent degree of privacy requires some additional work and/or compromise.
Password Manager
TL;DR - use Keepass.
VPNs
TL;DR - use MullvadVPN as it doesn't require any details for registration (your account is just a randomly generated number) and it accepts paying with cash or crypto (including Monero).
I should worth noting that VPN ads are quite misleading, and realistically most people don't need one.
Instant Messaging
TL;DR - if it's just you and a few people (like your irl friends), use GNU Jami. For larger groups or communities, use Matrix or XMPP.
Jami is the easiest for normal people to use (imo), but its peer-to-peer nature doesn't scale well with larger groups of people.
TL;DR - use something like Tutanota or host your own mail server
It's worth noting that email was not designed to be private or secure. The main appeal of email imo is universalism (since everyone and their grandma has an email address).
Operating System
This one is kinda finicky as the "best Linux distros for privacy" like Tails and QubesOS come with limitations that make them unsuitable for general use.
If you use some kind of free (as in libre) OS like GNU/Linux or FreeBSD, you're probably fine.
Not just a set of tools.
Privacy isn't just a set of tools, but a lifestyle. If you install a custom Android ROM only to run apps like TikTok and Instagram, it almost defeats the point of using a custom ROM in the first place. Especially since these apps are non-essential.