I pirated the "piano for all" video course and found it pretty easy to follow. It starts with basic rock piano from the first unit.

Aside from that, youtube videos with Keysight or similar MIDI visualisation plugins are a fun way to learn, compared to reading sheet music. I started with tutorials for zelda and animal crossing etc songs to keep myself engaged and it worked well, found myself wanting to just sit down and jam new tunes all the time. I just put my laptop into tablet mode and set it on my sheet music stand and pull up the videos, start at 0.25x speed and progressively increase speed as I get more comfortable with it

Take lessons. It doesn’t need to be weekly or even steady like when you were little. There are beginner piano lesson books tailored to adults, and having a teacher who can walk you through it, discuss your interests and goals, and answer your questions is worth the money, even if you meet once a month or just schedule per-basis when you feel ready to meet again. A local music shop can put you in touch with a teacher that knows rock.

And don’t give up when it’s hard. It’s hard to learn new skills. Trust that your brain accomplishing work in the background even when you feel like you’re not making progress, which will happen sometimes. One day you’ll wake up and find that the impossible chord progression you’ve been stuck on for weeks is a little bit easier all of the sudden, then it’s on to the next milestone.