"Once we are done, I will call"

English as a Second Language English Vocabulary, Grammar and Idioms
1

Is this correct sentence:

“Once we are done, I will call”
OR
Once we have done,I will call.

Regards

2

The first is okay, informally.
Formally ‘Once we have completed it, I will call.’

The second should be
"Once we have done it, I will call.

3

Thanks Beesnees, nice reply.

The Avatar of yours’ reminds me of the Quantum world, where small energy pockets (which, I believe, have some sort of consciousness), come into existence and go into nothing (void).

Atheists say, it’s a mechanical system, that’s it.
I believe the single consciousness maybe the God. Who has no name and shape at all.