I have found a bugg

Hai Mojang,
I have a problem with my Minecraft. I can get anything out of my inventory but still placing blocks / pillowcases. I Minecraft again instal on my computer. Only that did not work either. I do not know how I could fix this now. I would like to answer here!

Sincerely
Mees de Krijger
(MeesDeBadGanz)