Share Crunchyroll account?

If I open a Crunchyroll account with a friend, can he use the account and can we also watch quwasi at the same time as with netflix?

Yes, you can watch several at the same time at Chrunchyroll (self-tested).

At least two are possible. In addition, I have not yet tested myself.

Then how can I share that?

You create an account and tell your buddy the access data. In exchange, your buddy should regularly pay you half the cost.