It doesn’t matter where you start. Just start.
I completely agree with Reg.
As in Shard & Freude?
I did say "arguably". My own personal preference would be something by J S. Bach - by coincidence, this year is the 300th anniversary of the first performance of the St. John Passion. I think most Bach scholars would go for the B minor mass.But bear in mind that recordings of the Brandenburg concerti - which lay undiscovered on a dusty shelf until 100 years after Bach's death - were sent into space by NASA in the Voyager spacecraft as an example of what humans can do.