It really depends on your prior knowledge and what aspect of proteomics you are most interested in. A good starting point is here:

https://proteomicsnews.blogspot.com/p/resources-for-newbies....

Also, if you haven't already, maybe take a look at transcriptomics first, as there's more introductory material on this topic. For instance, there's an excellent online course at https://diytranscriptomics.com/.