Answer:
It is an infinitive functioning as a noun.
Step-by-step explanation:
I took the test and got a 100 , also it is an infintive functioning as a noun because "to + verb" = infintive and to begin is a nominal (noun) infinitive -- it acts as a noun. :)
Some example would be To travel the world would be my dream come true
My goal is to skydive over the Grand Canyon