In short, Christianity's primary hook to begin with...Satanic Panic. Everything in QAnon's worst nightmare boils down to Satanphobia. The pedos are a Satanic cabal. Commies are godless Satanists. Leftists/Democrats tend to be less Fundy/Evangelical Christians...and thus Satanic.
Qristianity is the age-old, viral reservoir here...QAnon is just one of its modern tentacles.
> How do I separate the real from the fake these days?
You need to develop your epistemic toolbox. Read some on skepticism, and critical thinking.
Sagan's The Demon-Haunted World: Science as a Candle in the Dark is a good place to start.
Also, here is a good website to get you going: 7 Ways to Improve Your Critical Thinking Skills.
If you desire companionship that doesn't revolve around politics or personal beliefs, then is trying to leave QAnon by seeking to join the "left-wing side" the best way to accomplish that? There are politics-adjacent groups that don't depend on personal beliefs like Rationalists, but even that doesn't seem like the best strategy. Something more like board game or video game groups seem closest to what you're looking for.
I think you might have a broader difficulty integrating into even non-political groups for a simple reason; no-one has ever taught you methods for talking about politicized topics other than devotion (when they come up, and enough topics are politicized that one always will). This is not a unique, or even unusual problem, its something that lots of people have (often inherited from their parents way of relating to the world). For example, how often do you hear questions like:
There are other methods to explore a politicized topic without even divulging what it is that you believe, or easier ones that still don't invoke devotion as a method and so don't isolate people. I might suggest The Scout Mindset by Julia Galef for an introduction to working in probabilities and confidences with regard to beliefs, as a way to talk speak with thoughtful scepticism to any "side" without isolating anyone.