I need more electricity in my garage. The breaker box is full, How can I add more?

You could add a sub panel. More info will get a better answer, like what your trying to do, what kind of service do you have, distance to garage. Good luck

I want to run more power to my unattached garage, and plan to add a swimming pool this spring, The garage is 45 ft from the house, The pool would be 100ft away but closer to the garage.Also would this require another meter?

Add more power? Is there power out there now? If so you cannot have two feeds or more than one circuit to a detached structure.

You haven't even answered the question yet about how much power you do have.
What is electric in the garage?
Since the building inspector has to be involved in something like a swimming pool anyway, why not have him look at your panel.
I see no reason why you need another meter.

Okay bare with a moment or two.

To begin with, you need to get a calculated load study completed by a licensed electrician.

1) Just because the main panelboard is full does not mean that you are maxing out your electrical service, particularly if you are at 200 Amp service.

2) You would begin this conversation with your local power company to see if they are equipped to provide the service you need.

3) You will have to supply detailed plans to your local Authority Having Jurisdiction in order to pull permits. In our area, only licensed contractors and electricians can pull permits for jobs except in the case of the actual homeowner.

In the case of the pool, permits will also have to be issued for that work.

With respect to the garage, you cannot run additional "Service" to the garage. However, if the cable from the main service is of sufficient size, you can increase the size of the sub panelboard or add sub panel to the existing configuration in the garage.

None of this work is run of the mill DYI work for an person unskilled in electrical work.

The grounding and bonding for the pool area alone is critically important.

But I would start would with the "Calculated Load Study" first.

Thanks, I was just looking for a starting point.