How do I procedurally generate a world with a tilemap

I am creating a top-down 2D survival game, and I am almost finished! But the hardest thing for me right now, is world generation. I am lost when it comes to arrays, so a dumbed down, but detailed explanation on how this works, would be amazing!

Thank you!

Hey StaticC!

It's not very clear if you want to create your levels in an array and read them to set the tilemap up or if you want to implement rules so the game procedurally creates maps by itself.

I want to implement rules so the game generates the map itself.