By now you have probably found the manual, read it and found there is no battery, as I did when I found and read this:
http://imagebank.indesitcompany.co.uk/brochures_online/pdf/Cannon/Cooking/CHICHESTER_MK2-01.pdf
If the clock (and maybe the oven light) are both working OK, that suggests the mains supply is good. If the clock isn't working, check there is power coming out of the wall - plug in a lamp or something.
Is there ANY noise when you try the igniter? Clicking like there is a spark somewhere?
Assuming power to the cooker is OK, that leaves just the ignition module or the pushbutton.
IF you are competent to check the switch and the ignition module and do any necessary replacement, that should be relatively straightforward.
IF you are competent. If not find a helpful techie
Spares are easily found with a Google search - like what you did to find the manual.
PS. It's "can't" not "carnt", September 2017
