Okay, I know this is another one of those nub questions lmao.

Couldn't solve it myself...

 

Is there a way to retrieve all blocks like Block.blockList or something?

It was removed in 1.7

Its now called Block.blockRegistry but you need to get the blocks by using a mapping key since it is using maps instead of an array now.

GameData.blockRegistry.iterator()

Don't use it in "regular" code, this is only one-time-searching method.

for (Block b: GameData.blockRegistry) {
    doSomethingWithBlock(b); // example code write this method yourself - or:
    b.activateBlockMethod(args); // use a real method
}
for (Item i: GameData.itemRegistry) {
    doSomethingWithItem(i); // example code write this method yourself - or:
    i.activeItemMethod(args); // use a real method
}