Samantha, welcome to the forum!
While you are clearing the land for a new pasture be sure to leave some big trees to give some shade for the goats and cows.
Knowing what part of the world you are in might help with grass recommendations for the pasture. We have folks from all over the world that will love to chime in when they find out you are in their country of state.
I would suggest using native grass for your area.
You might be able to find native pasture mixes at your local feed store or seed company.
You or others might find this thread interesting:
https://permies.com/t/20710/Mark-Shepard-Perennials-Started-Animals