Lost

I'm lost! I am new to SL and need a greeter and knowledge on how to explore this new world. Please help.

Orientation Island, I clicked home and teleported when I didnt know I would, and it said I couldnt go anywhere without finishing it but I did.
Now everywhere I go barely any people, usually none, and I bought clothes, try to "wear" them and a box appears on my body, not the outfit!! Someone says I have to rez it?? No clue..
I also saw no place to choose a greeter at set up.

Everyone does this, so don't worry too much about it. What you need to do is drag the item you want to wear out of inventory onto the ground (aka, rez it). A box or bag will appear nearby. Right click and choose 'Open' from the pie menu, then click the button in the window that appears to copy the contents back to your inventory. There is also an option to 'Wear Now' if that's what you wish to do. Make sure you pick up the container, by right clicking on it again and choosing either 'Take' or 'More>Delete.' Littering is rude, after all. Some places are 'No Build' and will not let you pull the box out of inventory, so be aware of that when you try. There will be a symbols at the very top of your screen indicating whether you can or not...hovering your cursor over the symbols will tell you what they mean. Not all purchased items require you to unbox them, though. If you have a folder with several items, or one item with a clothing symbol, rather than an object with a cube symbol, you should be able to wear without rezzing.

I believe there's a public version of Orientation Island you can return to for some of the necessary lessons...just use the Search button at the bottom of your screen and choose 'Places.'