God instituted the Catohlic Church to be authority on earth. Your question was how do you tell what is symbolic from what is literal. The answer is, read the commentary by the bishops and doctors of the Church.
“Eucharist” isn’t even found in the index in my Bible
Nor is "trinity" or "faith alone". Oops, that last one is in the Bible, where it is negated. The issue is not words but that St. Paul teaches the Catholic doctrine of Real Presence in 1 Cor 11.
There were true reform movements in the Church. St. Anthony, St. Athanasius, Leo the Great, St. Francis and St. Dominic were reformers. Leo XIII, Paul VI, John Paul II were reformers (we often wish the latter two were less so). Not all reform is bad, just a fake one undertaken in 15c by Luther and Calvin to destroy the faith of the Fathers. That is why it failed.
If the Catholic church is the “true church” why would they have to change anything? It would be pure like Christ, and nothing would need changing. Reform does mean change, doesn’t it?
Not just another dumb blonde,
You wrote:
““Eucharist” isn’t even found in the index in my Bible”
It’s in mine - and it’s not even a Catholic Bible.
And it most certainly is in scripture in its original form: http://www.searchgodsword.org/lex/grk/view.cgi?number=2169