2001 Jetta 1.8t shakes when put in drive and reverse

Hi I was wondering if you guys can help figure out what exactly is wrong with my car and how I can fix this problem. About 2 days ago my jetta started making a weird noise in the engine as well as the muffler. Everything was fine until when I started my car and when I put in drive there was extreme shaking. It does this when its in drive and reverse. The check engine light started blinking. It seems to have lost power. I'm not exactly sure what it could be. I got the diagnostics results and it gave me two codes:p0301 and p0412. Hope you guys can help I would really appreciate it. Thanks.