Is an online course for my business for $2997 deductible. How do I deduct that?

To be deductible, your expenses must be for education that (1) maintains or improves your job skills or (2) that your employer or a law requires to keep your salary, status, or job. 

https://www.irs.gov/taxtopics/tc500/tc513

If you are an employee, enter the education expenses in:

• Federal Taxes
• Deductions & Credits 
• Employment Expenses
• Job-Related Expenses

*This deduction is subject to the 2% rule on Schedule A.   

If you are self-employed, enter the education expenses 

• Business tab
• Profit or Loss from Business 
• Business Expenses 
• Other Common Business Expenses 
• Other Miscellaneous Expenses