Whats a good first book to read in the bible? I tried Romans but im struggling a bit.

First off, I struggle with porn. I battle it daily. Just today i fell again but just now i finished reading Romans chapter 4. I am not sure if cause im not always fully focused but i feel i cannot understand much of Romans. Are there "easier" books to understand that i cant start with? I don't read as often as i would like to but i have to start. Its the only thing that keeps me from watching any dirty videos. How can i focus more and get closer to God? I do pray before bed, when i wake up, and at most meals sometimes i forget if im really hungry. If I don't pray i feel kinda guilty. But i know prayer is not the only thing. I know i have to read but i can't focus all the time. Any tips to help me focus more? Thanks in advance.