How to populate other cells based on Drop Down Value (plus a couple other questions!)

Hello Hive Mind!

I recently inherited a spreadsheet that is not very useful and I'm trying to find a way to make it more dynamic and easier to use. I've attached a sample.

The main question is:

How do I populate other cells based on the value selected from a drop down?

For example...

On Sheet OT...

I would like for the "Name" to be a drop down. Based on what name is selected, I would like columns A, B, and J to grab the corresponding values from the table "Employees" on the Drop Downs sheet. (This is where the Name list is coming from).

Knowing how to do that, solves a couple of the other areas where I would want to do something similar (i.e. on the Shift tab, the drop down would be on the Earn ID and the Rate would populate)

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Another question I have...

Is there a way to automatically use a formula based on which item is selected from a drop down? Would that need to be set up similar to my first question? For example, on the OT spreadsheet, if the Earn ID is OTPR then the formula in column M should be =SUM((([@[Monthly Base]]+[@Shift]+[@Stipend])/173.333)*1.5) but is the Earn ID is OTST it should be =SUM((([@[Monthly Base]]+[@Shift]+[@Stipend])/173.333)*1)

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My last question...

On the stipends sheet, I have four columns (D,E,F,G) where there is a drop down. Each item in the drop down has a dollar value on the drop down sheet. Is there a way to come up with a total based on the drop down selections in those 4 columns?



I think that's it... I really appreciate everyone's help!!!