My advice to you is to use one of the following mouthpieces, whichever is most comfortable: Bach 7C, 5C or 3C. If you are a newbie, you don't need to look any further than those three.
Also, while I admire your enthusiasm, if you are truly new to playing, don't you think that it might be just a bit presumptuous, putting the cart in front of the horse so to speak, to plan on being a pro trumpet player at this stage of the game? Some of us have been at it quite a long time and are not "pros". What I'm trying to say is that while hard work will take you a long way toward that goal, you are also going to have to have a certain amount of inate ability, ie talent, to leverage toward that goal. It isn't something that just happens as a natural progression of playing and practicing. Most people will have to overcome a roadblock or two (or five or six!) before attaining the level of proficiency to play at a pro level. For some, it's range, for others, it fingers, and for others, it might be a sound issue. Sometimes hard work alone is enough to overcome the limitation, but in some cases, the issue has to be looked into from different angles and sometimes a whole new approach is necessary in order to overcome whatever playing obstacle is in front of you.
Best of luck to you and keep us posted on your progress.
