The only real knowledge we have is our immediate experiences; all the other stuff are just lenses thru which people interpret and relate to their experiences.
While I see what you're saying, I don't think that the
only thing we have to go on is personal experience. The scientific method is a very good tool for determining the true nature of reality, and it does this by eliminating, as best it can, personal experiences, "lenses", etc. It works, too. Trusting personal experiences has contributed very little of substance to the world. The effectiveness of the scientific method is evident all around us all the time.
However you or I might experience reality, there
is an objective reality. You and I might perceive the same event differently (in fact, we're almost certain to do so, even if the difference is only small, but create a hypothesis that's testable, replicable and which makes predictions and, as a community, it's possible to determine whether it's true (or, at least, consistently determine it's not untrue enough to make it being anything other than true extremely unlikely).