Online tutorials with playing techniques?

Hi beloved friend and community.
I probably asked this before, but to much drugs and booze after concerts made me forget.
I’m looking since a long time also to specialize my playing techniques, I’m not such a super piano player, more an allround Synth player.
But i would like to learn some extra skills and techniques.
For example piano key slides with thumb, special piano arpeggios, organ slides and techniques,…
But these tutorials are hard to find online.
Where do you guys find your sources? YouTube’s? Online courses? I’ve been looking, but can’t find any good stuff.

YouTube is usually a good place to start, even tho many of them are not correct. Your best bet is to use your eyes and ears, watching and listening to the greats. If I am stuck on something I want to learn, I might watch someone on YouTube, then watch the greats in live performance. Still trying to nail down Billy Preston and Corey Henry. Been working on Keith Emerson and Rick Wakeman on and off for 10 yrs. My 2 Cents.