[Help Please] Applying an already trained model to an image

Hello,

I am new to tensorflow and am trying to figure out what I think
should be a rather simple task. I have a model (.pb file) given to
me and I need to use it to markup an image.

I have two classes that the model was trained on: background and
burnish.

From this point on, I have literally no idea what I am doing. I
tried searching online and there is a lot about how to train a
model but I don’t need to do be able to do that.

Any help pointing me in the right direction would be
awesome!