I want to install a block heater on my honda accord 2004 L4 2.4l LX. I think i have found what i need to take out but am not sure what it is or how to take it out. Here i have some pics of what i have found above the oil filter. The blue plug when i move it back i see a yellow piece, what is this? Is this what am suppose to take out to install the block heater? If so How do i remove this part? Is the blue plug what they call the coolant drain plug also, to drain the coolant from the engine? Thank you so much for any help

Update:* Actually from what i understand now (in the last picture) above the red oil filter there is that deep hole and am suppose to unscrew whats inside and screw in the heater. Is this correct?