Hello! Querod520,
First of all, congratulation on your new endeavor! I am not entirely clear as to your corporation tax filing requirements as a "Professional Corporation," and I would recommend that you first of all refer to your incorporation documents filed with the Secretary of State in the state you incorporated in, as a Professional Corporation could mean something different in different states. Since you said you formed a corporation, I assume you mean either a C Corporation or an LLC ("Limited Liability Company.")
If your Professional Association is considered a C corporation according to your Secretary of State, then you would need to file and Form 1120 for the tax year. But I think you most likely formed an LLC. In this case, if you are the only shareholder in this professional corporation, you will just "need" to include your business income on a Schedule C as part of personal tax return; Form 1040. There would not be a separate filing requirement if this is the case. This is the clearly the simplest scenario for filing.
As for start up costs, you can deduct $5,000 in the first year, and amortize the rest over 5 years. You can include just expenses in your first year filing.