Step one is recognizing the cognitive dissonance, which you now have done.
The gospel, as given in Scripture, is that good news message that our salvation is a function of faith only, in Christ and what He has done for us.
But, there are many false gospels out there, and the most common type is through addition; adding things claimed as necessary and required in order to be saved, thereby falsifying the gospel in the process.
Many churches have done this. Many false preachers and ministers have done this.
Another process resulting in a false gospel is by re-defining words, terms, and concepts from the Bible. For example, do you know what it really means to repent? Like so many other words, there are nuances of interpretation and definition. Basically, it means to "turn to God." Many deceivers re-define it to mean "turning away from sin" as a means of getting people to start keeping biblical "law" as they define it also, and then you end up with a belief system that has keeping law in order to be saved also.
Hope this helped.