Hey, I just bought a Mac, I've been a Windows user for most part of my life and I usually use it through a lot of keyboard shortcuts
in windows I could move a windows with alt+arrow keys, how can I do that with mac?
I don't believe you can without some sort of utility to help you with that. I think New BetterTouchTool may help you in that, but I've never used that app, so I'm not quite sure.
I'm unsure if Spectacle does what is requested - but it's a freebie with donations welcome https://www.spectacleapp.com - although reading a little about it, it should be suitable.
Besides that there's a few other apps on the Mac App Store that does things like this - Magnet, Moom and BetterTouchTool(as mentioned) Probably more as it would have it. These apps or utilities on the Mac App Store often costs a little.