We get into this debate every time. A population of people can grow in any given geographical area as long as the carrying capacity of that area (eg food producing) is not damaged. It is sustainable if this growth does not endanger carrying capacity for future generations.
Then you have economic growth. This is often translated as Gross national product and the sum of all services bought. If a population is growing, GNP could be increasing whilst GNP per capita is falling. Then you could have a situation where a few rich are gettng richer and the rest are getting poorer and you still have high economic growth.
If we could give each other services without involving the eco system we could probably have economic growth in a sustainable way. Like playing monopoly. the more we played, the more we would turn over in services (hotel charges, rent) the higher GNP per capita.
Unfortunately that is not the case. For every kg of stuff you buy 30 kg of waste and effluent are produced. All that oil burnt up for ever! THAT is not sustainable.