Consider UK; 204 trees * 65 million people = 13.2 billion trees.
Woodland estimates there's approx 3 billion trees in the UK now.
That's over 4 fold increase in trees every year. I doubt the terrain/nature could support such a significant increase in just one year, let alone a number of years. But I like the idea of more trees.
This planting should happen one time, not yearly. Of course every dead tree should be replaced though. If there are 204 trees capturing CO2 for every human (and these numbers are correct) we should effectively be carbon neutral. No idea if that is even remotely realistic though