Tutanota, infomaniak, onion mail, forward email, i2p mail
set up your own hosting solution. it is not hard, i did it too. if you need a preset one, nextcloud, filen, cryptpad, cozy, puter, internxt, cloudreve, denet
not really, Bitwarden and KeepassXC are the most established ones. for the best security and privacy, i recommend (selhosted) Bitwarden, since if your computer with KeepassXC, or even just the drive you installed it on stops working, you lose all your passwords, which really sucks. This is not an issue with Bitwarden, the passwords are stored with zero knowledge encryption, you will have all your passwords until you know the master password, and can log into the same vault from almost any device (windows, mac, linux, android, ios, bsd)
Mullvad, yes. But there are some others like Riseup, Calyx, nym vpn
For calendars, there are a shit ton of them: My favorite is Foossify Calendar, but there are some others like: Tuta calendar, etar, kalendar, calindori