This lecture series by Martin Kleppman is excellent:
https://youtube.com/playlist?list=PLeKd45zvjcDFUEv_ohr_HdUFe... as well as his book “ Designing Data-Intensive Applications”
Reading trough the Jepsen analyses is also invaluable (not for the faint hearted, you might find some software that is dear to you absolutely torn to shreds in there): https://jepsen.io/analyses
Finally, all of the classic papers are worth a read: spanner, bigtable, google file system, dynamodb, chubby, dapper, the google paxos engineering paper, the main ones from Lamport… that said distributed system is a vast field, resources as far apart as the bitcoin paper or the original Shapiro paper on CRDTs might be of interest :)