This is cringey as fuck.

sorry for rage comics, but it isnt rage comic, it is squiptar comic

it is our serbian tradition to call pupils in school friends, like my friend mihajlo punched me or friends will play with me! how we will call them in english like that

well to all peope, our kids in serbia know what are the games, hardcore games that contain mature content!
wel everyone is teasing me. what are our kids in Serbia now!

On a side note, I've realized you're far more concerned about getting to level 7 than you seem to be about this person.

Alright, the biggest advice I have is remove the word "Friend" from the first paragraph. And now we may continue:

Now, Minecraft is not God. People who don't like Minecraft will not go to hell. So it is not vital to your existence to make him like it. If he were a real friend and still doesn't like Minecraft, be a big boy and suck it up. There are seven billion people on the planet, do you really think each and every one of them will like a video game?

With that out of the way, we can get on with how to treat this person in ways unrelated to Minecraft, because he's just as immature as you.

Mark Twain once said "Don't argue with stupid people. They'll drag you down to their level and beat you with experience." So, the answer is simple, ignore the brat. Sometimes taking their teasing like an adult speaks worlds more than reacting like a child. He'll leave you alone.

Also, don't watch Sky while you're at school. Don't let the guy near your home and know that Minecraft is not an appropriate subject while you're around him. In fact, that's what a real friend WOULD do if he knew someone didn't like what he did.

E.G. Muppets. I love Muppets, my friend doesn't, so I just don't talk about them while I'm around her unless their somehow relevant to the conversation. Find things you and this brat have in common, and make that a topic of conversation.

Also, you say he makes fun of the graphics. That's just plain old bully-stupidity and there's nothing you can really do about that.

He's not your friend if he makes fun of you for something you like

whatever you do, keep doing what you do, don't give in to teasing and insults, just try to ignore them or at least get them to understand that theres a lot more to the game then what it seems.
there are so many people playing this game ranging from schoolchildren to artists to professional mechanical engineers, from 5 years old to 70 years old... (i am 21 for example :) )

if they dont like the game then that is their choice, if they continue bullying, try to get an elder or authority to help you.
what you did however, resorting to violence (slapping) is never a good idea and can/will be used against you.
the only time that works is when people have tiny peas for brains and can only understand the wisdom of a good fist at that specific moment (way to drunk but still going to drive for example), but never start first, or try to start it at all, for it doesn't solve anything (unless it stops a rampaging drunk :P ).

anyways, this is just my $0.02 cents.