2002 Lexus ES 300 Air Fuel Sensor

Engine Mechanical problem
2002 Lexus ES 300 6 cyl Manual 89000 miles

My check engine light came on, I took it to a Toyota Dealership and they told me my Air Fuel Sensor was out and quoted me nearly $600 to replace it.

I went to Auto Zone to have the codes read and got P1150, and P1155 which relate to Bank 2 Sensor 1.

Is this something that is difficult to do on my own? It seems to be merely unscrewing and disconnecting the sensor and putting the new one on. Where do I look to locate it, and are there any adjustments that need to be made once it is connected? Or will it automatically sense the correct air/fuel amounts? Is the air fuel sensor the same as the o2 sensor or are these seperate?