Is English your second language? Your question is incoherrent. It sounds like you want to scale your file annamorphically. In the image size dialog box you can choose to resize your file in one direction without affecting the other by deselecting the chain link in between the two dimensions. Unfortunately, you mention percent and pixels in your posting. In the image size dialog box you have to commit to one or the other. You could create a new file and then enter your exact dimensions in pixels. Not sure what "style with CSS" means. It sounds like you could benefit from the many online tutorials available.
Oh no sorry i guess i just did not explain my self better. I do apologize, i've seen so many images, in a div, that looks to see if it has a 100% width with x amount of height with pixels. sorry for the
inconvenience, English is my first language lol =). i was trying to see if Photoshop does that kind of feature when you take the chain link off. i have tried to do so but does not seem function the way i would like it to. Unless i am missing something or i am doing something wrong
An image file only knows its own absolute dimensions, not a percentage. If you want an image to fill 100% of the width of a CSS DIV, you cannot save that information with an image file; it must be specified in the CSS style controlling the DIV containing the image.
When you see 100% in Image Size in Photoshop, that refers to the percentage of the image before resizing. So 100% there means no change in that dimension, and that 100% only has meaning while resizing or transforming in Photoshop.
Perhaps better asked in the Dreamweaver forum, or similar.