to find out what young people think about the future of urba

to find out what young people think about the future of urban life,a teacher at a univerty --句子成
To find out what young people think about the future of urban life,a teacher at a univerty in texas in the united states asked his students to think how they would run a city of 50000 people in the year 2025.前面to不定式做主语吗,那find out是谓语了,what后面是宾语从句?是这样的吗,不是的话,to不定式是什么,在整个复合句中做什么
还有To get rid of garbage problems，中的to又是做什么？