Connecting TV to receiver via HDMI
If (as seems likely, but you don't tell us what TV you have) the HDMI on the TV is (are) all inputs, you will have to use optical (or some other audio - coaxial digital, for instance) output.

If the TV has HDMI outputs, you might be able to rig something where one of those goes to an input on the reciver, but that might not work with having the picture on the TV screen, depending how it's set up.

BTW: Don't fall (seriously) for gold-plated optical cables - the working part of the TOSlink optical cable is a plastic fiber optic. They don't need to cost much, but some sharpies have preyed on the "audiophool" market and produced (uselessly) gold-plated versions to part phools from their money. Cheap ones work just as well...