I need to declare my business expense
See this TurboTax support FAQ for entering self-employment business expenses - https://ttlc.intuit.com/turbotax-support/en-us/help-article/import-export-data-files/enter-self-employment-business-expenses-like-home/L1k6HJY4A_US_en_US?uid=m903jkdw
Please follow the instructions in this TurboTax Help article on Where to enter your business expenses.