CAPTHA-Stuck in Rules

Hi Everyone, I hope You all are doing well.
I’m a Mikrotik user for around 8 months,I did blocked some sites and users were having access of internet. Now my company want’s to allow some of the sites only and block the access of internet. I did tried many rules but some sites are using captha and other security stuff, they’re working but unable to get the work from them. Do anyone having any solution. Your kind responce will be appreciated.
Thanks