Deductions & credits

How can I calculate to figure out whether my FTC exceeds allowable? Never happened before, & I don't know how I could possibly know whether or not my FTC would exceed what I'd be entitled to if they were US Dividends? Tax code is written very poorly & I don't trust Turbotax I think it has one rogue.

 

Can someone explain to me why I am paying for Turbotax if I have to figure out FOR MYSELF how to calculate?