Multi Blog Login Issue (changing default link on main page)

So i set up a new database and was able to get a second blog setup for my wife at https://www.carriessweetlife.com I even found a link here to help me set it up. However Now I need to figure out how to get her logged in. The main issue is the link on the new blog is the dafault link, it goes to the main root directory, I need to change it to look in the new folder for that login php. I can edit it in expressions but I am not sure how to save it and upload it or which file I am changing.