After seeing the death of Peter Parker with his own eyes Miles decided to pursue the SuperHero lifestyle which started with his first supervillain encounter with Kangaroo. After winning this battle Miles was captured by Spider Women who addressed him on wearing a Spiderman costume while fighting crime which was in "bad taste" due to the death of spiderman aka Peter Parker. After questioning Miles Spider Women decided to arrest him and take him to the S.H.I.E.L.D headquarters this is where Nick Fury reveals that he knows all about Miles and even knows information about his family including his uncle's criminal activity. While at S.H.I.E.L.D headquarters Miles was able to capture the escapee villain electro which proved his worthiness. Nick Fury then releases Miles and gives him the Black and Red version of the original Spiderman costume.
After a few more superhero battles Miles gets acquainted with aunt may and Gwen Stacy they give him peter's web shooters. A few Months after obtaining these web shooters he begins training with the original Avenger himself Captain America. In the Ultimate Spider Man #2 issue Peter Parker confronted Miles about being spider man which caused them to have altercation this lead to Peter finding out about miles venom shock Peter then Punched Miles causing to black out.
After the bad blood between them Peter and Miles eventually Made up and started to work together. Miles is now in the main Marvel Universe Fighting alongside Peter Parker and the Avengers.