Premiere Elements 12, Adobe's video editing software geared toward non-professional users, is your best bet if you want to create and edit a video project with your webcam using Adobe products. In fact, the ability to capture images from your webcam is absent from the professional version of Premiere, so to record from your webcam directly into Premiere, you must use Elements.
The Add Media panel is the tool you use to import video clips and other media into your Premiere project, and it's also what you use to capture from your webcam. Access it in the top left part of the main interface. Choose the "Webcam or WDM" option to reveal the capture window, and then select your webcam as the source of your video in the "Capture Source" drop-down menu. Your webcam's view should be visible in the middle of the window if you've configured it correctly. Title the content you'll be capturing in the Clip Name field, and use the Save To field to choose its location on your hard disk.
Use the "Full Motion" radio button in the top right part of the capture window to record a typical video. Unless you're recording a silent video, make sure your webcam's or computer's microphone is selected in the "Audio" drop-down menu. Your webcam's view is visible in the center of the window, and you can start recording by clicking the "Capture" button. Click the same button to stop recording.
In addition to regular video recording, Premiere offers a different capture mode that only records one image at a time instead of video. It's typically used to make stop motion animations, where many small changes to a scene are presented in a sequence to create the impression of motion. After activating the "Stop Motion" radio button, click "Create New Stop Motion" in the middle of the window. Once you've arranged the scene in front of your webcam, click "Grab Frame" to capture the first image. Make small changes to the scene, and then click "Grab Frame" again. Repeat this process to gradually create your animation.
Once you've finished recording video or have captured all the frames of your animation, close the capture window. Your new clip appears in the project timeline and the project's assets, and can be immediately incorporated into your project just like any other media. Be creative and experiment -- for example, make an animation with Stop Motion capture, and then capture a video to create the soundtrack, or combine multiple videos and animations into a single composition.