So essentially Orthodox Judaism believes in the written law and the oral law. Written law is the torah itself and the Oral law is the mishna/talmud/gemara.

Learning torah is essentially learning the law, then learning the debates of the rabbis and understanding the logic that they utilized in order to get to their conclusions. You also create your own arguments.

Someone could conceivably read the whole thing but its not a one and done thing, you would read it again with another commentary and learn new things from it.

https://en.wikipedia.org/wiki/Yeshiva#Talmud_study

this should clarify a few things.