You can mess about with sugar bruised ginger stem, lemons and stuff if you want
.But, the easiest way is just buy a white wine kit, add an extra 250 gram of sugar and
25 gram powdered ginger.
Make the kit as normal but add the extra sugar and the ginger straight to the demi john.
Then just follow the instructions, except: when it stops fermenting syphon off into a clean demi john before you add the finings etc.
It's best if you sweeten it a bit, usually between 55 to 100 gram sugar