RawPower

What do I click to convert the path from outline to closed path?

So do I make it look like the picture above?

Sure. Here it is. Octopus.afdesign

I still can't make the line rounded even though I selected the Round Cap for some reason.

I was wondering if Affinity Designer could add a feature that makes the ends of lines rounded. I looked for a post on how to create rounded edges, but I wasn't able to find a post on how to round the edge of the line drawn below. Is there a way to make the edge of the line below rounded in Affinity Designer? If not, could it be added as a feature? Thank you for considering this!

I was wondering when a perspective tool might be added to Affinity Designer. I know it's available in Affinity Photo, but it would be helpful to have it available for use in Designer. I am open to feedback on this suggestion.