Fuschias grow mainly into bushes. They are not climbers. I could make some suggestions for plants that will grow tall but you do not say where you live. This is very important information as some fuschias are hardy ( will withstand light frost), others not. More info please.

There are two species I have in the garden that grow tall. Not true climber but can be secured to a fence or trellis. Regia/regia will grow to over 12 feet; Regia/rietzi to 8 feet. These are winter hardy here in the PNW although some really cold winter may kill the upper growth; they will regrow from the crown.

Realwendy, the one sold over here as a climbing Fuchsia is 'Lady Boothby'. I've only seen one example growing and it doesn't exactly climb. It has very long lax shoots which need to be guided and tied in. It's considered hardy in much of the UK. It is in flower now but remember that in the winter it will be just bare stems and not much good at camouflaging your fence.