"Autotext?" - simple question

[Ponderosa65]

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,

[RudiS]

I find this behaviour you describe rather odd?

If I start to type an entry that exists further up the column, Excel proposes the completed word to which I can either TAB to move immediately to the right, or ENTER to move down. In either case, it completes the word and moves.
I can also select a blank cell in the column and press ALT+DwnArrow and Excel creates a drop down list of entries available. I can then use my mouse or the arrow keys and enter to which Excel accepts the word and enters it into the cell. The selection stays on this cell until I enter or tab.

[shg]

There's description of an add-in that you might find useful at https://app.box.com/shared/4qxybepxxr. If so, there's an example file to play with at https://app.box.com/shared/e8dbbple34, and the add-in itself is at https://app.box.com/shared/ono8ni9xvr

[protonLeah]

Excel Options > Advanced > Editing Options: After pressing Enter, move Right...

[newdoverman]

If you want to accept the auto fill, hit the tab key to go 1 cell to the right. If you want to accept the auto fill and stay in the same cell, use Ctrl + Enter. You already know about the Alt + Down Arrow. The suggestion by protonLeah is also useful.