Actually, the silhouette on the start page of Merlin is a Merlin, Falco columbarius, a small falcon widespread across the Northern Hemisphere. But, they look a lot alike.
There is no limit on how long you have to complete the course. Work at your own pace and enjoy yourself. You can come back to the course again and again after you finish. Have fun.
Yes, that's a Chipping Sparrow. However, it's an abnormal one with an albino-like white patch on the face. Things like this happen relatively frequently, so beware of big white patches, especially if they're not symmetrically placed on both sides of the body.
@Lynn
No, there are not videos on every page. Every lesson has a brief introductory video. Each lesson consists of several topic pages but most topic pages do not have videos.