sorry that this sounds dumb but like... where do i submit my predictions, and where is the information stating what I'm predicting on?
Well you have multiple options to get there:
1) on the frontpage click on the prediction league header.
Then you will arrive on http://www.vgchartz.com/predictions
Next step is choose a round to enter, which currently displays only one option right now weekly wordwide chart 14th april 2018 http://www.vgchartz.com/predictions/enter.php?game=259
Which filled in looks like this