Expenses associated with your 1099-MISC income are entered in the same section as your 1099-MISC income. They end up on a Schedule C and reduce the amount of your 1099-MISC income that is taxable. Those expenses should definitely be entered since they lower your net income that you pay ordinary income tax on and your self employment taxes.
Charitable contributions and medical expenses are an itemized deduction and are entered on Schedule A. You can either use the standard deduction or itemized deductions on your tax return but not both. Unless your itemized deductions total more than the standard deduction, TurboTax will automatically choose the standard deduction for you. Only the amount of medical expenses in excess of 7.5% of your AGI can be deducted as an itemized deduction. There is no need to enter itemized deductions unless you think the total might be more than the standard deduction.
