Coming from small BTC buys, what should I learn before touching crypto or micro index futures?

I've mostly been buying small amounts of spot BTC and trying to learn the ropes without making expensive mistakes. Lately, I've been reading up on futures, especially micro contracts because the leverage and structured risk interest me. However, I'm absolutely not planning to trade anything live yet.

Right now, I'm trying to wrap my head around the core mechanics: contract size, tick value, intraday margin vs. maintenance margin, and actual risk.

I feel like a lot of beginners just look at the low intraday margin and completely underestimate how fast a position can wipe them out.

For those who started in spot crypto and transitioned to (or added) futures, what was the biggest "aha!" moment or the sharpest learning curve for you? If you were to start over in a sim account today, what's the rule 1 you'd drill into your head?