(CO2 produced by humans) = (number of humans) * (C02 produced per human)
If (number of humans) is zero, then (CO2 produced by humans) is also zero ... ignoring the CO2 produced by what we leave behind after we're all dead, anyway.
If (C02 produced per human) is zero, then (CO2 produced by humans) is also zero no matter how many humans there are.
In 1977, when the global population was 4.23 billion, emissions per capita were 1.19 tonnes of carbon per person.
By 2017, when the global population was 7.55 billion, emissions per capita were 1.34 tonnes. This over a time when most major economies reduced their output.
That means (7.55/4.23)*(1.34/1.19) = almost exactly twice as much CO2 is being produced by humans now as was being produced in 1977.
The United States is still the largest producer of CO2 per capita of all the world's major countries, by far. It is producing 16.24 tonnes per capita (down from 21.20tpc in 1977). China is producing 6.98 tonnes per capita (up from 1.37tpc in 1977). The UK is producing 5.81 tonnes per capita (down from 10.74tpc in 1977). And, as stated above, the global average is 1.34 tonnes per capita, so we're all well above that.