Why does the instruction booklet show $12400.00 for the standard deduction, but you show $14050.00? why the difference?

are you 65 or older?  You get an extra 1,650 = 14,050.

Filing Single and you are age 65 or older your Standard Deduction is $14,050

Standard deductions for 2020

Single - $12,400 add $1,650 if age 65 or older
Married Filing Separately - $12,400 add $1,300 if age 65 or older
Married Filing Jointly - $24,800 add $1,300 for each spouse age 65 or older
Head of Household - $18,650 add $1,650 if age 65 or older

See the tables on page 1 for Standard Deduction amounts and page 24

https://www.irs.gov/pub/irs-pdf/p501.pdf