Offer Letter

I’ve recieved offer letter from capgemini and one more will get it in this week. I have a few question:

1. Can i forward the offer mail and offer letter as it is recieved from other company. Or something needs to be hidden before sending.
2. What’s the possibility that they will revise with increased compensation or revoke it or keep the existing
3. If i get any letter since i have a month to join, should i ask for the negotiation again or it will be risky? Note: I’m inclined to join an MNC