Herkese iyi günler

How can one say "must" and "should" in Turkish. For example:

He must be replaced immediately.

I should go home now.

You must listen to me.

You should listen to me.

Also, how is it possible to say "able to" in Turkish. For example:

I want to be able to speak Turkish well.

I wish to be able to walk again.

he wants to be able to drive as soon as possible.

Çok teşekkürler

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