From what you say the child lock is on. Without a model number this makes it a bit harder to know which you have but try this first and see what happens and let me know.
Press and hold the picture of the padlock for about 10 seconds or so and see if this turns the lock off.
Try that first and see what happens and let me know.
Nice one glad to hear thats sorted it.
The model number will be on a sticker on the underside of the hob. So if theres an oven under there or a drawer you need to remove them and then you can access the underside of the hob and get the model number from there.
Once you have the model number go to Bosch's website and you can download the manual from there.
If you could also remember to rate the answer that would be great.