First off, no, steampunk and clockpunk are not the same thing.
Steampunk and clockpunk have been considered many things: genres, aesthetics, movements, lifestyles… But I would define them largely as genres, of which aesthetics, movements, and lifestyles can emerge from.
At the most basic level, steampunk is subgenre of speculative fiction and science fiction, that is situated in the Victorian time period and emphasizes steam-powered technologies.
On the other hand, clockpunk is also a subgenre of speculative fiction and science fiction, but it can be situated in any time period and emphasizes clockwork technologies (such as springs and cogs).
This diagram specifies how steampunk and clockpunk are situated in relation to each other and some other genres.
*Keep in mind that this diagram omits other subgenres and only focuses on the relationships between the four presented above.
While steampunk and clockpunk are separate genres, they can, and often do, overlap. So you could have something that is strictly steampunk, or you could have something that is strictly clockpunk, but often times the two genres are blended in popular culture.
This website will explore, in depth, how the two genres function together and separately.