I suck at science, so apologies in advance. I know we are all made of atoms, and atoms are made of quarks and something else? But I wondered, if you break each thing down and down, you must eventually reach a base particle? Like the building block for EVERYTHING in the universe? Any ideas? Does it exist or is it theorized?

Again, I suck at science, so I would greatly appreciate any answers to be in 'laymans terms' and metaphors are always good.

Many thanks - DM.