2004 Cadillac Deville code p0130 P0135 p0174 p0300 p0446 what do I do

Question

What's the steps in trouble shooting these codes, it runs fine I felt a lil shaking when at stop lights so I cleaned around the intake valves yet I still have all these codes please help

Comments

I know it can be my O2 heater sensor, or my spark plugs or coil pack or fuel injectors or vacuum leak and bank 2 is running lean just need some good advice