Calculate a date dervied from 3 cells + calculating the amount of spec days.

Can anyone help me create a formula for these three problems? Thank you in advanced to anyone who takes the time to help me!

Problem 1
I want to calculate a date derived from the month name, the day, and the year in cell D2 & D3 respectively, but D2 & D3 need to remain empty until i enter in data in A2:C2 & A3:C3.

Problem 2
Then in cell F3 i'd like to have the total amount of Tuesdays & Saturdays between the dates in cell D2 & D3.

Problem 3
I want to drag the formula in F3 downward, but i want it to remain empty until i enter an end date:

Example: F4 needs to remain empty until a date is entered in D4.

Try these

D2 and filled down
=IF(COUNTA(A2:C2)=3,(A2&" "&B2&", "&C2)+0,"")

F3 and filled down
=IF(COUNT(D2:D3)=2,NETWORKDAYS.INTL(D2,D3,"1011101"),"")

how do i change the formula in f3 to any specific day? say i want it to be wednesdays and saturdays instead of tuesday and saturday?

That's where this string comes in
"1011101"

That is a string of 7 1's and 0's representing the 7 days of the week, beginning with Monday.
0's are counted, 1's are NOT counted

So Wednesdays and Saturdays would be
"1101101"

got it, so just change it to correspond to the string as desired? thanks

Yes

You could even use a cell refernece there, say H1 or whatever.
=IF(COUNT(D2:D3)=2,NETWORKDAYS.INTL(D2,D3,H1),"")

Make sure H1 is formatted as TEXT to preserve leading 0's if used (if Monday was a day you wanted to count).
Then you could use data validation on H1 to make a list of all possible strings you wanted to use..

little confused on the last suggestion

instead of hard coding the 7 digit string into the formula
=IF(COUNT(D2:D3)=2,NETWORKDAYS.INTL(D2,D3,"1011101"),"")

You can put that string in a cell, say H1 for example
=IF(COUNT(D2:D3)=2,NETWORKDAYS.INTL(D2,D3,H1),"")

And put 1011101 in H1
But that cell H1 needs to be formatted as TEXT.