You can do it bit by bit. Start by switching to Firefox on desktop and mobile (if you're an Android user). Install Firefox Multi-Account Containers to sandbox Google and other surveillance capitalism products. Switch to another provider for your email, contacts and calendars. I chose Fastmail - it's adequate. The best thing I can say about it is that it has a suite comparable to Google mail, calendar and contacts and there's no evidence it's tracking me. I use Thunderbird on the desktop and the Fastmail app on mobile. I've moved all my contacts into Fastmail.

Use hooktube (and Hooktube Redirector) on desktop and mobile and NewPipe on mobile. Favour apps from F-Droid. Install uBlock Origin on desktop and mobile.

My next moves are to get my calendars out of Google (my wife and I have several calendars we've shared for years) and into Fastmail. I need to get a couple of years' worth of photos out of Google Photos and back into Flickr. (They probably have a brighter future now that they've been rescued from oblivion by Smugmug - though Ipernity is probably another decent option for a classic Flickr experience.) `rclone` will probably be a lifesaver there.

I need to find a solution for hosted files and docs; I've not found Nextcloud to be convincing. I use B2 for offsite backups. I've yet to install a pi-hole, though I already have a pi doing DHCP and name resolution for my home network. I often use sshuttle if I want to become opaque to my ISP. I have a PIA VPN account but it's consistently terrible - could be my ISP mucking with the traffic.

It's going to be a multi-month project. I look at what I've done and have yet to do to evade constant casual surveillance and I strike myself as sounding like a tinfoil hat conspiracy theorist - but I'm not. I'm just a rational citizen, attempting to recover for myself some of the human rights I took for granted a decade ago.