I wonder if any one could let me know how Minibits and other cashu e-cashes work?

How do I redeem e-cashes to sats?

How much does it cost to redeem my e-cash?

(where can I find the fee table?)

Can I redeem directly to BTC?

Do I need a separate cashu wallet except minibits?

Or could you provide any video link with which I can find out these?