Why are mortgage rates in USA so high compared to Europe? What are the main reasons of high mortgage rates in USA compared to central Europe? In central Europe mortgage rates are about 75%-100% lower than in USA.

For data on mortgage rates see:
https://www.numbeo.com/cost-of-living/country_price_rankings?itemId=106
The European Central Bank has held interest rates to an extremely low level, in large part in an attempt to boost the economies of member countries in the wake of the most recent worldwide financial crisis.  The United States economy has had a stronger recovery, and so rates in the US have risen in recent years.

This article, "How Europeans' household net worth is 'now exclusively driven' by negative interest rates" provides some detail and explanation as to why rates in the EU continue to be held to such a low level.