Choosing an iCloud account for a new MacBook Air

hi i am just wondering i am in the process of buying a macbook air and this would be the first one i have bought so im not that sure on if i should add it to my phones iCloud or to a separate icloud and add it to my family account because i have a separate icloud account for my ipad thats on my phones family and that works perfectly fine but i am worried that i wouldnt be able to log into my icloud mail or my passwords on the macbook or even mirror my phone to my laptop . but on the other hand my icloud on my phone is full enough as it is and i would rather not add work files on top of that and i dont want my photos on my MacBook aswell as its unprofessional i think