How can i make a jpeg image have the quality of a png one. Becuase im trying to upload the image to a site. However that site only takes jpeg images. And of course its really blurry.

Thanks in Advance

Well, save it as a jpg with 100% quality. It shouldn't be too bad unless your original image is blurry.

Moved to Webdesign

If you have Photoshop click "Save for Web" or something like that. There you have all of these options. It'll show you a preview of the final image. It'll also show you the potential size. All you have to do is play around with the settings util you're happy.