You should try France or Germany if you're looking for a place without Arabs. The Dutch aren't really renowned for being open racists, and therefore have very few segregated areas, especially in a capital city; you're going to find different cultures no matter what country you go too.
It's going to be difficult to avoid Arabs in Amsterdam. They are part of the society. They work in restaurant, stores, tourist attractions, etc.
The majority of the Arabs lives in the western parts of Amsterdam.
There are no racist rules in the Netherlands. You will find people of all colours and creeds in all parts of the country, even in the small places far from Amsterdam.
I do not know why someone answering here thinks that might be different.
If your father can not face people with a different genetic background than he finds at home, he best stays at home.
In the Netherlands, also in Amsterdam, he will find them everywhere.
And that is no recent development although numbers have changed over the years, Amsterdam has always had a fair share of foreigners of all parts of the (then) known parts of the world.
Good luck to you with that.
You might it easier to stay in one of the smaller towns outside of Amsterdam, but there won't be nearly as much to do.
