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How can i make a surface that sits inbetween these two curves?

Answers
if it's all in a sketch, the reddish area should be clickable and be usable as a face as is. (for an extrude, loft or whatever.)
no further action required.
If it selects more than that reddish area, it means the lines aren't fully closed. you can use the 'sketch diagnostics tool' to trouble shoot. (Button next to the 'Final' button)
f you really need it to become a separate surface for reasons i cannot think of, then first make a:
fill with the outer contour.
Split face with the inner contour,
delete face on the inner face
I think i forgot to clarify these are all registered as curves; they aren't sketch entities. I used Projected Curve on a flat sketch to use Offset at 0mm (sketch) but because the face is made of… like.. 100 curves i couldn't click all of them… Now that i think of it i should've simplified it to splines to make a single curve…
All this was an attempt linking back to my other post of trying to wrap around an object similar to a sphere. I forgot exactly how i was trying to achieve it, but in moment i thought if i wrapped it around an axis, projected it to be flat, made into a sketch entity, wrap around reference cylinders, then repeated for all the axis, it could wrap it as a surface and Thicken it then follow the process shown in "TEACH PRODUCT DESIGN"s video where they emboss/deboss irregular non-wrappable round things.
One day i will figure out.. One day my silly little hyperfixated brain will find a solution for reliably wrapping around non-cylinders!!!
I should probably try to document my process in an example that others can find easy to follow so the problem can be solved easier,,,