Roughly how much Co2 is generated per kWh of electricity generated
About 900 grammes of CO2 for each 1kWh of electricity.

There is some variation: very modern super-critical coal plants can be lower. But 900g is a reasonable central estimate.

Note that that's just CO2 from combustion. It can be higher, when we include CO2 and CH4 emissions from the rest of the coal supply chain too.