You don’t need Criterion or Mubi to watch great classic films! I recently discovered that Tubi, a platform that you not only don’t need to pay for, but don’t even need to make an ACCOUNT for, has a rotating wealth of classic films, from famous to obscure.
Just watched Un Chien Andalou, now watching Riders of Destiny. The other week I watched Sherlock Jr.
Film school is great (as someone who went) but you can give yourself a great primer yourself by watching some classics for free and then reading/watching some critiques and analysis of what you don’t understand.