I tried to play on minecraft 1.9, but its telling me to close the launcher and open it to download?

Do what it says

Just don't play minecraft. Grow up and mature. Go out. Meet some girls. Have fun instead of locking yourself away. I used to love minecraft, their realised what happened to it, and the other day I saw my 9 year old cousin playing it and he got so immersed, I realised it was just sad.

Just delete it entirely and redownload from their website. You can backup any maps you want to save if needed.