Yes. It is typically followed the by field of study. For example, "I hold a Bachelor's in English." If you don't use the field, then it is probably more common to just say "have," instead of "hold." But I think either one would be grammatically correct.

Yes, or I have... or I have earned.... But be careful how you format Bachelors, Masters, or PhD, as there are many ways to do so, and many countries have their own special format. See the bottom of http://www.thefreedictionary.com/_/dict.aspx?word=bachelor's+degree and http://www.thefreedictionary.com/_/dict.aspx?word=master's+degree