How does the ranked system work?

I completed my 10 placements and was placed into Plat 2.
Is Plat 2 higher than Plat 6?
I saw there were rewards, but I don’t see anything. Is it end-of-season stuff? Or am I missing something?

Plat 2 is not higher than Plat 6. You get up to Plat 6 and then the next rank is Diamond 1. It’s a little confusing. An in-game notice when playing ranked would be a nice touch if they haven’t done so already.

1 is bottom tier and 6 is top tier before next bracket.