right front Inner burner doesn't heat

Glass top stove - the large burners have an "inner" and an "outer element".

The right front "inner" burner element doesn’t light.

Thought I’d just be buying and plugging in a new burner element -
then wondered - "just the get the inner element of the burner?" –

then I was told it may be the switch on the panel that switches between just the outer element or both the inner and outer elements heating –

but the diagram shows one switch on the panel (part #4) and 2 other electrical parts (parts #6)

How do I tell if it’s the element or the switch needing replacement.

If it’s the element — should I just look for the inner element - is the inner and outer element both part of a single unit?

If it’s the switch — "since the panel show’s a picture of two circles - inner and outer circles - on the left of the switch (and a picture of a single circle on the right of the switch)does that mean I need the just part #6 for the left side?"

The wife is really looking for me to get this fixed - HELP!