Etesync provides end to end encrypted contact, calendar & tasks.
DecSync CC combined with syncthing lets you do the same peer to peer to other devices without using a server
Cryptpad is a good alternative to Google Docs - especially if you need to do live collaborative editing.
For general cloud storage lots of people use Nextcloud (including me). Its OK and pretty user friendly. Theres lots of places that can provide Nextcloud. Through working on different projects somehow I've ended with four different Nextcloud accounts set up on my phone. The folks at https://disroot.org do a pretty good job. They also host their own instance of cryptpad - among many other services. They also have pretty good tutorials how to set up all the various apps on phones and PCs.
For the sake of security some people dont like the complexity, design or bugs of Nextcloud & suggest using a simple webDAV setup on a NGINX server or similar. Never come across this being offered as a service, but it wouldnt be difficult for someone with sysadmin experience to provide.
Could use the webDAV mounts feature of DAVx⁵ or possibly better use the Android rclone client rcx (or in future, once it hopefully has a stable release its successor extRact to have your files encrypted before they are sent to webDAV (or other) cloud storage.
For rcx and extRact need to enable the SAF client and content provider previews to get it all nicely integrated into the GrapheneOS system Files app and file pickers.