How COVID-19 has affected car makers
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Do not write any of your language translation, as your brain will be fooled in storing it as a synonym in your language.

As in context

Demand for - increase in need for the semiconductors by car makers.

Step up - increase production of semiconductors by car makers

Here it means, to increase dramatically.

Bounce back
A return to normal after a difficult situation.

Fill their need
Here car makers need to be provided with what they need badly.