Moments? I'm pretty sure it takes much longer. At least the way I remember as a child visiting my grandparents in the country.
Step 1. Get up at 4:30am, go out to the barn grab a small stool and a pail.
Step 2. Give old Bessy a reassuring pat. Sit on the stool and position the pail and grab an udder in each hand and start milking. (Note, if it's a cold winter morning, you need to warm up your hands a bit because Bessy can give a kick if your hands are too cold. Mind you there is nothing like leaning your head on Bessy's warm side on a cold winter morning).
Step 3. Let milk stand for a few hours. The cream naturally separates and accumulates on the top. Skim the cream off the top, separate and save for other use. (My Grandmother used to make her own cheese!)
Step 4. Cool down the milk for a few hours.
Step 5. Pour milk into glass and drink.
Nothing like fresh farm milk.
If you want to pasteurize, you would have to add another few steps where you briefly boil that milk before you cool it. I should add, I have no idea how to make low fat milk out of this. But then why would you want to?