I'm trying to fix up a friends bike and cannot get the front derailleur to shift.

The bike was bought second hand so I can't be sure exactly what's on there and what should be on there. It definitely has ultegra rear derailleur, 10-speed cassette, and 10 speed 105 shifter (the rear shifting is fine). The front had a much older crank than I would have expected and wasn't as spec'd for the new bike; I replaced that with a modern double crank. The front shifter feels like it has three clicks but it's a little sloppy and I can't tell if it's just 2 clicks and a trim. The front derailleur is an FSA energy (looks like about a 2006). The cage looks wider when compared to a new Ultegra.

The cage doesn't seem to pick up the chain; it doesn't move far enough. Is it possible that the derailleur is for a triple and is there a way to get that to work on a double?

Many thanks,

Tom

Do u know what limiting screws are?

Yes. That is not the problem.

All 105 shifters are double/triple compatible, there are no differences within a generation (like 10-speed). A triple front derailleur can work with a double crankset but not as well as a double front derailleur. Yes the triple FD will be wider rail-to-rail.
My best suggestion is to use the derailleur adjustment instructions found at https://www.parktool.com. Be sure to do each step in proper sequence. Be sure the derailleur is low enough and properly positioned.
Instructions are also available at https://www.shimano.com.
Cleaning out the insides of STI shifters with WD40 often improves shifting performance. New shift cables and cable housings can also improve shifting.

Al