This is a dumb question and a simple one but...I can't find the solution and it drives me nutty.

I keep Excel spreadsheets to track purchases - eg groceries.
One column is to identify the vendor. Since I use a number of vendors frequently, when I start typing the vendor name, after typing 2-3 letters, Excel brings up the whole name. This is a great feature.
However, in order to choose the vendor name that pops up, i need to use my mouse and click on the pop up. But.... then the cursor jumps down to the cell below. So I need to use the up arrow or mouse to get back up to the correct line.
To me this defeats the purpose - i want to be able to hit a key to select the option Excel is giving me and then hit TAB to go to the next cell and enter the dollar amount of the purchase.

Is there a key that does this? If I hit return, it does not select the whole name, it leaves the first 3 letters I typed, and then bumps me down to the cell below. If I hit tab it also leaves a few letters.

It doesn't make sense that one would need to use the mouse as it interrupts the flow of the process.

Hopefully this is s simply "D'uh!" question that someone can answer easily,