I was in four different Protestant Churches in my younger years and have spent a good deal of time in a fifth in my later years.
Certainly I've had a great deal of teaching on what the scriptures mean.
Believe me, these churches were far far from the same. If you asked me which one is the True Christian Faith and teaching? How can I say? They're different, some very different.
But on essentials, they were likely very similar. Practice, secondary doctrines, yes - we can be quite different. But who God is (at the basic level), what salvation is, what Christ did - more similar than different.