Do Christians believe that God is a white Caucasian man?

You'd need to firstly study what a Christian is, as then you would no doubt recognise there is no such living thing, only many humans who self claim to be falsely.

YHWH God is not physical and has never been a man of any colour, only the son Jesus was ever a man, Jesus is not the Father.

Jesus said that "God is Spirit" (John chapter 4, first half).

Jesus, as the Son of God, added human nature to His divine nature via Mary, and "the Word became flesh[human] and made his dwelling among us... And we have seen his glory, that of the only-begotten of the Father, full of grace and truth" (John chapter 1, vss 1-14).

As a human, Jesus was Jewish (Matthew 1:1-17) and He would have looked like all the other Jewish men of that era. See the link for that. The Father, however, remained in Heaven while Jesus the Son was on Earth for a few years. And God is Spirit.

Some do. But then some people are stupid.

Also, in Moscow, Caucasians (people from the Caucasus) are referred to as 'blacks', especially those who are Muslims.

Some do, depends on how you got brought up for him to believe he looked like, Jesus for exsample, was techniquelly born in Israel, and the majority of their people are black, so I believe it would make sence for Jesus to be black, but some prefer to be as closely relatable to Jesus as much as possible, and some paintings are him white and some black

Hi yes i believe most have that image. personally it is more likely to be a large west indian mother with a warm heart.

Yes they do. Christians are pretty 'gullible' generally !

God is not a man, the Bible makes that quite clear.

A lot of them do. Blame the renaissance artists for that one.

Yes from what ive heard.

Absolutely, complete with board shorts, thongs and zinc on his nose..