That sound like a huge pain. It sounds like one of the apps that you're using is probably pushing popup ads to your phone. Often free games from questionable developers use overly aggressive ads to try and make money (popups, ads in your notification bar, etc).
I'd recommend trying this app, Ad-Network Scanner by Lookout (the same company that makes the anti-virus software). It scans every app on your phone, tells you what ad network they are using, and what they can do (for example put ads in your notificaiton bar, change your browser homepage, add icons to your desktop, etc). Here's the link: https://forums.androidcentral.com/e...ails?id=com.lookout.addetector&token=SO2Eg8Q3
Keep in mind, everything that shows up in this app isn't necessarily bad. Free apps have to make money somehow, so many show ads. This app is just to inform you what app are doing what things. That being said, I personally would uninstall any app that can do any of the 4 things on the list (ads in notification bar, change browser homepage/bookmarks, add icons to desktop, or start the camera, SMS, or phone call on ad touch).
Edit: By the way, I forgot to say Welcome to Android Central! This is the best and most helpful Android Community on the internet. I hope this works for you.