You only speak for yourself when you say, " We know with certainty that church claims; 'beliefs are truths', based on first centuries fixed doctrines and dogmas are anything but. They are based on myths, superstitions, and magical thinking.."
That is merely your opinion of which which you cannot have any certainty unless you are claiming to be infallible. You criticise the doctrine of infallibillity simply because you personally don't like it. On that basis you expect the rest of us to ditch 2000 years of teaching by Apostles, Evangelists, bishops, popes, doctors of the Church, Councils, saints, etc and just take your word for it.
You accuse the Church of being error whereas you just make up your religion on the hoof.
You say the Eucharist is a medicine but some medicines don't work, even do harm unless the system has been purged first; in this situation via the Sacrament of Penance.