How to stop my text/iphone from showing on my mac

OK so i Just got a mac book air and its just so diff from regular laptops and I just can figure so many things out ugh hopefully i will get used to it right?

ok so when ppl text me or I send a text sometimes it comes up on my laptop WTH? Like i think they synced it w my phone so that the imessage comes on the screen here and there… Does it do that for you too? How do i make it so my laptop and iphone have nothing to do with each other? Like I know when it comes up I can x it out but I wanna completely make the separate so no text or imessage etc ever comes on my laptop

Well maybe if you have a iphone is it? If so then you have to make a new icloud account