Adobe has several things that might help on their AdobeTV site, go there and search around.
Basically you'll need to use the Media browser panel (a tab in lower-left quadrant) to navigate to your images, select them and right-click "Import". Then set up a timeline with settings you'll be using for output (unless you do have actual video to use also, then just drop that onto a new timeline). Go to the preferences and set a default value for number of frames you want still images to become when you drop them on a timeline (multiply desired appearance time by frames per second of your timeline see below). You'll have to set the reduction of still images to your timeline's frame-size also.
You want to see each image for 1/2 second on a 29.97 timeline? Multiply .5 x 29.97 = 14.95 ... so give them 15 frames. Choose however long you want them to appear. Sometimes one wants them one image per frame, often somewhere between 2 frames and a second of time per frame.
Most welcome ...