Feeding and housing them though? Absolutely doable. It would require a significant change in our societies, but we know enough things about the universe to accomplish this.
If you're saying, politically, this is impossible, sure, you're probably right.
This is a ‘the entire world economy is based on fossil fuels, and attempting to redo the entire worlds economy to use non-fossil fuels is not currently doable’. Even the best case emergency scenarios would have to use even more fossil fuels to try.
Germany and California have tried elements of it, but even despite massive investment they are still heavily dependent on fossil fuels for almost all the baseline parts of their economies (transportation, heating, industrial uses, etc).
If we all went on a wartime footing and devoted our entire economies to completely retooling the worlds economies, maybe - but realistically, it’s clear that people would rather blow each other up (which will also solve this problem a bit !) than do that.
And a big reason why is a lot of people are likely to starve to death or be pushed into poverty to attempt it.
But, it's not like we need fossil fuels to farm, and there's already enough housing for all the humans. If we engaged in expropriation, it's certainly physically possible.