There are only two prepositions in this sentence, and those are for and from.
Prepositions are parts of speech that show us the relations between words. For example, location, time, etc. Some examples of prepositions would include words such as in, out, under, above, from, without, etc.
The word to mentioned in the sentence above can be considered a preposition in this example: I am going to America.
But when it is part of the infinitive (to submit), then it is not considered to be a preposition, but rather an infinitival marker.