The "ads not by facebook" showing up in your facebook pages means you have installed some "malware" that is inserting the ads, you need to run an antimalware scanner such as malwarebytes antimalware to remove the rogue software:
if you also want to get rid of official facebook ads in the side column or the sponsored posts, you can remove them by installing the FB Purity browser extension which has lots of cool features for blocking unwanted facebook content from your screen. You can get FB Purity here:
I think you must install a malware in your system without notice. To block those ads from popping up, you should find out this malware and remove it completely. If you need any help to get rid of this annoying malware, please feel free to contact www.DooFix.com to ask professional PC experts for help.