Bq is right on how the starter system works, my bet is that the wire in the headstock has stretched and iif you turn the bars from side to side the bike will start.
Common bandit/motorbike issue.
The other possibilities are easy to trace and replace.
I agree with Jung
Cheap bindit
https://www.gumtree.com/p/suzuki-motorbikes/bargain/1169600135
Now can you see what is wrong with this bike:
https://www.gumtree.com/p/suzuki-motorbikes/suzuki-bandit-road-bike-/1171704127