Can i gain booty muscle and get thinner upper body ?

Hi, i have a normal body for someone who doesn’t really work out but it’s healthy, standard. My upper body is slightly disproportionate and i want smaller shoulders and lose my arm fat, which is a lot compared to the rest of my body. In general i’d like to lose some weight to achieve a skinnier body, however i want to build my glutes and i know in a calorie deficit i won’t progress on gaining booty muscle. Can i achieve the body i want? What should i do first? I started the gym this year.

Thank you :)

Edited