I walked too much today, my legs feel like sticks...

*sniffle* *sniffle*

From now on, let's ride Mr. Horse!

*neigh*

You know that your big sister can't ride a horse!

Oi, where do you think you are from...?

Well then, let's ride a dog sled!!

But if it's before snow piles up then you can't ride it, can you?

I'm ready, let's fucking go I'm ready, let's fucking go

Right then, are we gonna go?

If you're going to go, you've got to do it properly. This is rather difficult to translate and who Satori is referring to is a bit ambiguous. It, along with what the huskies are saying, are in reference to this panel from the manga 動物のお医者, which is somewhat of a meme.

Big sister is such a party pooper!

Hey, I'm sorry that I can't ride... This is a pun on のる, to ride. The idiom ノリが悪い meaning party pooper is lit. "bad at 'riding' (going along with) [the fun]", and here Satori apologizes for not being able to "ride". This can be interpreted both as apologizing for being no fun in reference to the idiom, or literally not being able to ride a horse or a dog sled.