Others have already provided answers, but I strongly believe that anyone who wants to study Vol 1 will benefit so much more if you start with some primer of classical economics/political economy that covers Adam Smith and David Ricardo.

Marx’s Capital Vol 1 is simply the continuation of those works and he assumed most of his readers at the time were already familiar with Smith and Ricardo. Marx transcended those previous works by bringing class analysis and dialectical materialism into the mix and bringing the Smith and Ricardo’s theories of capitalism to its logical conclusion, but he doesn’t exactly hold your hand on topics he assumed you should already know!