What apps do I need to create and upload animations like Snoopy on my Apple Watch ?

Are you asking how to get the animated, Snoopy watch face on your watch? If so, then assuming your Apple Watch is paired to your iPhone, to upload the Snoopy watch face,

1. Open the Watch app on your iPhone.
2. Tap Face Gallery at the bottom of the screen.
3. scroll to find the Snoopy watch face, select it, customize the color then tap Add.

I do not think it is possible to create animations for the Apple Watch. If I am wrong, someone else here can step in.

You can only use the animations that are already on your watch, unless you;re going to develop for watchOS

There might be some third party apps with that kind of animations but I don’t know of them

You need to become an Apple Watch developer then.

Nuahla wrote:

Thank you I’ve figured that much but paying $99/year to become a dev and not knowing what is possible for a simple html, JavaScript programmer/graphic designer like me to do is a bit of a gamble. There should be apps and beta testing outside the dev program ? ...

The primary advantage of a paid vs a free developer account, is that the paid account can put their apps into the App Store. The free account can do everything else, except publish their apps in the App Store.

Snoopy is copyrighted intellectual property. It is highly likely that Apple's license agreements don't allow anyone else to work with the character.