The answer is yes you indeed can. to add an image just click the image icon on the editor when composing an answer or question. Just keep in mind we won't host the image for you, use free image hosting sites.
Free Image Hosting:
There are plenty of them out there I could go on for days.
As for the videos, you simply paste a youtube video URL into the text editor on NQ, and the site turns it into a video. Eg..
Hope this helps.
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