What version do you have? You can enter Self Employment Income into Online Deluxe but if you have any expenses you will have to upgrade to the Premium version. Or use any of the Desktop Download programs.
How to enter income from Self Employment
https://ttlc.intuit.com/community/self-employed/help/how-do-i-report-income-from-self-employment/00/...
You don't enter losses. You enter the actual income you received and your expenses. Turbo Tax will figure the Net Profit.
Where to enter business expenses
https://ttlc.intuit.com/community/entering-importing/help/where-do-i-enter-my-self-employment-busine...
Self Employment tax (Scheduled SE) is automatically generated if a person has $400 or more of net profit from self-employment. You pay 15.3% SE tax on 92.35% of your Net Profit greater than $400. The 15.3% self employed SE Tax is to pay both the employer part and employee part of Social Security and Medicare. So you get social security credit for it when you retire. You do get to take off the 50% ER portion of the SE tax as an adjustment on 1040. The SE tax is already included in your tax due or reduced your refund. The SE tax is in addition to your regular income tax on the net profit.
Here is some IRS reading material……
IRS information on Self Employment
https://www.irs.gov/businesses/small-businesses-self-employed/self-employed-individuals-tax-center
IRS Guide to Business Expense Resources
https://www.irs.gov/forms-pubs/guide-to-business-expense-resources
Turbo Tax Self Employed Tax Hub
https://turbotax.intuit.com/personal-taxes/self-employment-taxes
Turbo Tax Self Employment info
https://turbotax.intuit.com/tax-tips/self-employment-taxes/beginners-tax-guide-for-the-self-employed...
