It goes from high to low no problem, no clutch so assuming it is the belt, i will try that first thank you for your help

Bought this 5 months ago done 5 miles in it, decided to sell, been told it does not shift gear when moving stays in first, i had not realised
as i am a woman, He said it may be because the speedometer isnt working so not realising the speed to change up. i have no idea where to take this to get it seen to or where to start, i live SN7 way any help greatly appreciated.  i was sold the vehicle like this, the engine light is on however engine sounds okay and runs alright