Scrum Master Estimation and stuff.

Why would Joe do such a thing? From your reading of the Scrum Guide, who ought to be accountable for managing stakeholder expectations and for maximizing product value?

The situation, as described, leaves a lot of questions:

• The Product Owner may have created Product Backlog Items, but are they defined clearly to all relevant stakeholders, especially the Developers?
• What is meant by "all user stories"? The Product Backlog is an emergent list - the contents and their ordering will change over time.
• How did the team decide to use story points to size the Product Backlog Items?
• What is meant by "awarded to the team"?

Getting to some of the key questions - communication of the Sprint schedule and cost, there are other questions:

• Have Developers been identified?
• Does the Scrum Team have all of the necessary skills to do the work before them?
• Has the Scrum Team selected a Sprint length that is no more than one month in duration?

Once you have identified a Product Owner, a Scrum Master, and a group of Developers, it should be very straightforward to start answering these questions. As soon as you have a Sprint length or cadence, the schedule for when reviews and potential delivers becomes clear. The cost is also a function of the Scrum Team and Sprint length. By executing Sprints and carrying out the inspection and adaptation of both the product and the processes, some of the other questions will become more clear or evolve over time.

Scrum uses timeboxed events for the purpose of consistency and to instill discipline.  A Scrum Team should be a consistent group of individuals that are self-managing and self-organizing.  Addition/removal of team members would be disruptive so that is usually avoided by self-managing teams. So, taking those things into consideration, a Sprint could be considered a fixed cost.  In past companies where I have worked that required budgeting or costs for billing, a set fee was established for a Sprint and each Sprint was billed as separate projects.  The stakeholders, whether it be external or internal, would pay for each project until the time that they deemed the work was completed. This gives the stakeholders more control over the expenses. 

Everything else you brought up is irrelevant.  Story points have no bearing on the amount of work that is actually done and you are completely misunderstanding their purpose.  The Product Backlog will never have "all the stories" because it will constantly evolve to include everything that is needed for the product, well past the initial delivery and into maintenance and enhancements. 

The timeline is the fixed duration of the Sprint. The "confirmation from the stakeholders" will occur in the Sprint Review where the plans for the Product Backlog are discussed and updated with the stakeholders present.

Since you are new to agile you might want to improve your knowledge of Scrum. Scrum is a framework that helps companies be agile but it is not the only one.  The Scrum Guide (https://scrumguides.org/scrum-guide.html) would be a good place for you to start your discovery.  Take some of the open assessments available on this site (https://www.scrum.org/open-assessments/scrum-open, https://www.scrum.org/open-assessments/product-owner-open, https://www.scrum.org/open-assessments/scrum-developer-open) to start gaining knowledge of the various roles of the Scrum Team.  There are also a number of discussions in this forum that could help you better understand. 

I applaud you trying to learn and hope that you are succesful.