STEP 1: Import the raster image into Illustrator
Import the image you want to convert to a vector artwork by navigating to File >Place.
STEP 2: Trace Image
To create your vector, select your image, and navigate to Window >Image Trace. Make sure you have chosen the Auto-color setting at the top of the panel. After choosing it, click Preview to see how your tracing will appear like.
After you are satisfied with the Preview result, click Trace.
STEP 3: Expanding the Image
Once, you finalize the design so that you can work further, navigate to Object>Ungroup. Ungroup the image twice, make sure to navigate Ungroup for a second time too.
Nonetheless, you will now be able to alter your vector according to your choice.