I would add that the illiteracy is a symptom of overall poor cognitive function, although it's hard to distinguish from his preference for telling lies and bullshit wherever possible.
Case in point: Raking the forests.
It could be seen as a stupid (clever?) spin in order to discuss climate change and federal responsibility.
However, lose the optimism, and it looks like the statement of a man who's 1. Never been outside of a city or into an actual forest, 2. Is unable to imagine one, or the simplest implications of his suggested policy 3. Cannot correctly understand the policies that the Finnish leader was describing, not recognize his own gross misunderstandings of the real world.
Ie, he lacks the mental power to even know what he doesn't know, and lives in an alternate, fantasy reality.
Beyond the typos, his words don't make sense as his reality doesn't make sense to normally functioning and informed human beings.