If you watch films based on classical works, then it is better to focus on those that were shot by Soviet cinema, since at that time the best human qualities reflected by classic authors in their works were highly valued. Today this theme in cinema is so blurred, and sometimes even replaced by not the best examples, that the main idea of the work is lost or washed out, to the greatest regret. Reading is certainly better. You can agree with the author in some way, you can disagree. Through reading, the personality of the author is better visible, images appear in thoughts - their own, and therefore they are more lively and understandable. Reading classics is not always easy, but always useful!
A good program in Russian and Soviet literature was, of course, immense and, frankly, overwhelming. A big role should have been played by language teachers ... But, alas ... If there is a desire to start mastering Russian and Soviet classics on your own, then ten or twelve works are enough ... A word about Igor's regiment; Woe from Mind; Belkin's stories; Hero of our time; Auditor; Crime and Punishment; War and Peace; Old Isergil; Twelve; A cloud in pants; Mother's letter; Quiet Don. And also watch their film adaptations. And most importantly - get a good general notebook, where you write notes about what you read and what you saw ... Good luck ...
Watching movies and reading the original are two different activities. The point is not to quickly learn the plot, but to read, reflect on the work, or on the movie you watched. A screen adaptation is a director's view of a given work, which may differ from your perception. So read and watch. Literature and cinema are two types of art.
Read books, definitely.
But if you don't know how to read (sorry, I didn't mean "you don't know how to read." Only literary scholars can really read, and even then not all) ... it's just scary to tackle a great work, you can prepare your own perception by watching a good film adaptation.
For example, "War and Peace" by Bondarchuk. There are several adaptations, but all of them are not about this, not about Russia, although some are quite good. But ... one day I decided to watch the latest "imported" film adaptation, a series that I carefully rewrote. I turned on the computer, and got to our home (I have all the classics for daddies). It was a scene when Prince Andrei, who was leaving for the war, said goodbye to his father (Andrei - Tikhonov, old prince - Ktorov). And I have already prepared for the new English version. I just missed - compared to ours, the British seemed, let the sweetest and smartest of dogs forgive me, mongrels. Yes . The British tried hard and played well, but they had no idea what a Russian person is ... So start with Bondarchuk.
I highly recommend Schweitzer's Little Tragedies. There is such Vysotsky (his last film role), Such Jurassic, such Smoktunovsky and all the others.
Wonderful "Snowstorm" by Basova.
Books, of course, are the best :-) But if it's difficult, then you can watch movies. There are good adaptations of Pushkin, Lermontov, Goncharov, Tolstoy and Dostoevsky.
Sometimes there will be better screen versions of books. I can definitely say this about the Russian TV series "The Idiot" and "Crime and Punishment". The works of Dostoevsky were perfectly filmed. And the actors very well conveyed the whole atmosphere of the book. I recommend watching.
To be honest, at one time I read a significant part of the school curriculum "in abbreviated form", on any sites where the plot is transmitted over several pages. To understand the essence of what was happening, this was enough, and we were not asked more in the classroom. Some of it made up at the university, some books after graduation, I have not yet reached some classical works.
So it all depends on why you need to make up for the school curriculum at all. Are you still studying and want to get to know the plots quickly? To be honest, most of the films based on books did not go to me, and some film adaptations distort the plot. It is impossible to study the works or biography of Gogol on the film-series of the same name, for example.
Some films take longer to watch than to read the works on which they are based, so saving time is also not always possible. For example, "Scarlet Sails" is easier to read than watching "Assol" from 1982. The same applies to performances based on Chekhov's stories (they were shown to us in class at school, and IMHO, it is easier, more interesting and faster to read stories, may the lovers of Soviet cinema forgive me).
If you want to tighten up the missed knowledge, then it is better to watch from the timing and your interest. Of course, books are always preferable - after all, the primary source. But if reading is hard and there is no time at all, and there is no time to educate yourself, the films will do quite well, and it is possible that some will inspire you to read books. Of those I personally liked, I would advise "Cruel Romance" (based on Ostrovsky's "Dowry") - again, in the lesson we watched the film adaptation, and this inspired me and many classmates to get acquainted with the original. Bulgakov's "Heart of a Dog" - well, this is already a classic, and I saw her at the age of 10, long before they began to study at school. "Quiet Don" and "The Brothers Karamazov" - if you do not have a reverent attitude in the spirit of "cinema is a castrated version of literature!", Better look, Soviet film adaptations are good and give a complete picture of the plot, and time is saved. In the end, if some story hooks, you can always read the original - the classic is not afraid of spoilers)