First off welcome to civ
when you set up a New Game you get 9 different basic land types to select from (from left to right on the set up game screen)
Pangea (1 large land mass) with 80, 70 or 60% ocean,
Continents (usually 2 large landmasses and some islands) with 80, 70 or 60% ocean,
Archipelago (loads of islands with maybe 1 or 2 larger landmasses) with 80, 70 or 60% ocean.
So for example a world with 100 tiles would have that % of tiles as nonland squares. So the bigger the ocean the less land and more bunched up everyone will be.
Land tends to get lumped together to allow you to build, there are only occasional inland seas on most maps.
you can also select world size on this screen from tiny to huge. This dictates how many tiles the world will consist of and therefore how much room eveyrone has. bigger maps also support more opponent Civs.
You can also change the world terrain settings to have lots of warm type square eg desert and jungle to cooler ones like tundra. As well as how wet the world is eg jungle to how dry eg desert. Age then determines how the land is 'mixed' older worlds will have terrain of one type more often grouped together and young worlds are more mixed up.
I think most players would agree a Pangea type map is the easiet to go with as you will get to meet other civs and hence trade with them plus you dont have to worry about a navy. However, everyone has their own preference and you will find yours by experimenting with the settings.
