How is your business set up? Is it a sole proprietor/self employment that you need to file on Schedule C in your personal tax return? Or is it a separate Business entity like a Partnership or LLC or corp or a Single Member LLC set up as an S corp? You need to file a separate business return for those.
If you need to file Schedule C for self employment you need to amend your returns to add it.
How to Amend the current year 2024
https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-federal-tax-return-current-year/L7eS6o1qh_US_en_US?uid=lfunevhk
How to amend a prior year return
https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-change-correct-return-already-filed/L4VjJ9BA2_US_en_US?uid=lpzqr4fi