Im struggling on starting to get the transfer function here any ideas on how to start?

 

You have a divided feedback that gives gain, and a voltage divider on the input that makes an attenuator.

Check the Ebook material - http://www.allaboutcircuits.com/vol_3/chpt_8/5.html

 

Assume that the input current to the op amp is zero and that the inverting node (V-) and non-inverting node (V+) voltages are equal. Find (V-) from Vo by using the voltage divider rule. Then say that (V+)=(V-). Find (V+) with respect to Vin and then equate (V-) and (V+). Finally, rearrange as to find Vo/Vin.

 

Also, R3 is irrelevant. It will not appear in the transfer function (assuming an ideal op amp).