In Latin, the phrase "I am" is best translated as "Sum". This is the first person singular form of the verb "to be". This would then be added to another noun or verb (as in "agricola sum", meaning "I am a farmer").
The word you are looking for is "sum" (which is pronounced somewhere between "soom" and "some" if you are saying it aloud). It is the first person singular of the verb "esse" (to be). [I can't think of anything else that's pertinent to add that will bring this answer up to the 50 words required! ]