i'm new to sweatflix and last week has been all about butt week but I'm not sure how can I find those videos. Can you please point me out in the right direction? thank you :)

Since no one else has answered, I´ll try to help. But first have to say that I´m also new here, so I am not a pro and don´t have much experience.
If you´re not doing a bootcamp and want to train a specific muscle group, I would simply use the search function. For the butt as example I would search for 'glutes'. You can also find the right videos under 'Workouts by type'.
But I don´t think that focusing a whole week on one muscle group is the best idea. A muscle can progress the best when it gets a few days off after a hard workout. Thats why the bootcamps usually don´t focus on the same muscles for two or more days in a row.

Hope my input helps. And if there is someone who knows better, you´re wellcome to correct me...