Welcome to the forum!
Not to panick I suppose your new battery is like this one in the picture below. Your old battery was sitting this one needs to lay down.
Just lay down the battery so that the text in the image below with big white + and - signs and PB recycle sign is on the TOP and your positive terminal will be on the right side and the negative on the left side. The text in the picture saying "This battery is filled with acid." must by upside down front vertical battery side facing you.
This means that when laying that battery on its side in the tray the (+) terminal will be located on the right side top corner which will let you connect your cables to it