Need help with dynamic recruiting dashboard

Hi - see attached recruiting dashboard that I've started. There is a lot of data input that needs to drive the dynamic charts and scorecard you'll see. I need help!!

Here is what I envision:
? People will input numbers into B4:AU4 and B6:AU15
? Based on the drop down date selected in B17...:
o The Recruiting Funnel Graphs should update with the corresponding/appropriate data B6:AU15 (one graph for operator data each week and the other graph for maintenance data each week)
? The Baseline Headcount Graph should update as more data is input into B4:AU4

I think it's some sort of offset function or index/match, but I can't figure out how to bring it all together.

Recruiting Dashboard.xlsx

For Operators, =INDEX(6:6,MATCH($M$18,$3:$3,0))
For Maintenance (Mech + Elec), =INDEX(6:6,MATCH($M$18,$3:$3,0)+1)