If you're referring to the exterior of the spin basket and interior of the outer drum .... run the tub clean cycle with an appropriate product such as Affresh or Tide Washer Cleaner. Otherwise, disassembly is required to physically reach those areas for scrubbing if the cleaning products don't provide sufficient results.

I’ve used both with no improvement :( how do you take it apart? Is that something we can do or do I need a repair person?

I strongly advise that you don't attempt to disassemble the machine unless you have a very competent DIYer in the household.

If you're specifically referencing the tub cover which your drawn arrow is touching, it's cleaned by you via wiping with a cloth or scrub with a toothbrush. Running the tub clean cycle has no effect on that surface being that the water can't fill that high without causing a flood.