I need help!

I would like to know how to load a seperate map.

My situatuion is this:

I am trying to make a map where there is one small one for character selection, and then other big maps.

I want to make the small char. selection map load the bigger map that will be the first level (this is an RPG btw, my first one.) I also want the char. they select to load in the first level map, too.

If this is single player then use Game cache. This has to be a campaign. So in your editor goto campaign editor, player all the maps .w3x into the campaign manager, save the campaign as w3n file.
To use the game cache. You have to create it first, then store data in it when you need so before switching maps. Then you save game cache and load another map. etc. etc.

This will not work for multiplayer

Thanks! thats just what i needed!

If i wanted to be able to do a multiplayer version, how would i do this?

also, i dont know how to make your selection carry over to the other map.

This totaly doesn't work in multiplayer. Best thing you can do in multiplayer are save/load codes that players have to write down and type in the next map. Game cache can be used for storing units between maps only in single player campaigns.

As for your second question, store the unit (hero) that is selected and load it into the next map.