Why won't Google Playstore download anything?

[AC Question]

I recently downloaded flash player for android tablet and that's when it happened. Nothing is working on my tablet. Especially Google play store, I wanted to reinstall apps so they'd stop force closing and I couldn't install it again. When I click "Install" on an app from the PS, It goes straight to downloading and that blue bar thing goes on forever. The notficiation in the top left corner comes after about 5 seconds when normally it'd come straight away, and if I cancel the download the notification still doesn't go away! It still says it's downloading it, even if I close PS. I've tried resetting, clearing cache and data, and also attempted to sign in and out of PS but I don't know how to. I have over 12000 people waiting for me to publish a new chapter on my book and I can't even install the app I write it on, I think I have a virus but I can't even install an anti virus, because it doesn't download! I really don't want to factory reset so how do I stop this?