Birthday Card

Hello, I bought a digital license for a vector image that I was going to play around with by figuring out which color to use for the background. However, I’m decent with using photoshop, but not so much with Illustrator. It contains 2 layers. The first layer is how I want my image to look, So I first thought I’d hide that layer to see what the 2nd layer contained....So after I hid the first layer, I got a “Transparent” checkered background left showing. So I thought, then I’ll just select the 2nd layer and either delete or hide it, but when I did, my birthday card clear balloons changed to black. The file came to me as a .eps and I lost all the layers and sub layers when I open it in Photoshop.. I’ve read only that I can export my .ai file to a .psd file and retain the layers, and subs, but I read that I must select cmyk, however when I do, it defaults to flatten all layers. I would like to keep the first layer and its sub layers and still be able to use it in Photoshop, but still retain a normal transparent background, so that I can play around with different colored backgrounds, in a new layer labeled Background. But if it would be faster and easier, if layer 1 could be removed so that only a transparent background exist, without the clear balloons changing to black, I’d be fine if it was saved that way in Illustrator. I was told that since this was a vector image with a transparent background, anyone familiar with Illustrator, can fix this within a matter of mins. I can’t seem to figure it out due to my lack of experience with Illustrator. This is a card I’m making for my mother for her birthday and I’m almost out of time to finish it and mail it to her, so I’d gladly pay someone to help me with this.