Do you mean how to see the beach? Because this is not how you get to it.
Oh I thought it's through there haha. How to though? 100% trophy?
It has to do with the breakable blocks you see at the ending. You basically need to trigger the last step of the home spell as soon as you start the ending sequence
How though? For ending you need to go to left, left alone verticallyEdit: okay, managed to use the home spell, but still no secrets being unlocked - I just go straight down.