If they are in the middle of the desert instead of giving them food each year making them depend on help invest that money in irrigation and agricultural gear.
The Netherlands has 1/10 of the arable land Niger has with almost the same population but they are one of the largest exporters of food!
And all this thing about poeple in poor regions not having enough food brings the one really interesting question, how have these poeple survived till date without food wand how is that there are still millions of them and still multiplying at insane levels, for example in Mali with a fertility rate of 5.6 or Niger at 6.8? What have these poeple done before the UN was even created?
Unfortunately the reality is that if you just give them land and tools, they won't do better. Nowadays agriculture works really good only if the same entity has large lands, hence affording all the tools/machines needed, from tractors to fertilizing gears and all that's needed for irrigation too. The smarter ones even do some processing of their harvest before selling, meaning animal farms and/or processing factories...
And on top of this, I would not be surprised if Netherlands also imports food (which they process and then sell).
Also, about fertility rate: usually religion and, even more, the lack of education leads to that. Just look at the numbers in Europe, for example. The more developed the country is, the lower the rate. Is that good? I wouldn't be so sure. Maybe large scale migration fixes that somewhat, but that usually means war which I don't wish to anyone.
Now back on topic: the problem is that all that population is not in one place, hence multiple investments would be needed, exceeding greatly those 6bn.
Maybe then something like what @Mauser said before: investment in some large farms and also a distribution network. Of course, this is clearly not "learning to fish".
And I also agree with some other posts here: is this really about world hunger, or it's about advertising UN and Elon? I guess that's somewhere in between...