You use whatever is greater. All your itemized deductions or the standard deduction. If you are making regular contributions and you are also taking minimum distributions from IRA you can consider having your IRA make the contribution. This way you get the tax deduction for the charity PLUS the standard deduction.
If I understand you correctly, under itemization, only my charitable contributions count, not like the old time a couple of years ago, when I got 2 x $6,000 for my wife and I just for filing and then another 2 x $6,000 for both of us being over 65 and could still take my charitable and property taxes? Or should I just use turbo tax and let it figure it out? I”ve used turbo tax for several years, except for last year when I retired plus moved and sold/bought houses...for that I got an accountant to do my taxes.