I don't know why you think there is a minimum of $10,000 for charitable donations. Charitable donations are an itemized deduction. In order for them to make any difference in your tax, your total itemized deductions, including the donations and any other itemized deductions that you have, must be more than your standard deduction.
For 2018 the standard deduction is $12,000 if you file as single or married filing separately. The standard deduction is higher for other filing status, or if you are 65 or older, or blind. The standard deduction amounts are slightly higher for 2019 because they are adjusted for inflation. VolvoGirl listed the standard deduction amounts for 2019. Your standard deduction could be less than $12,000 if someone can claim you as a dependent. In that case it is not a fixed amount. It depends on your income.
