Don't let anyone tell you you can't do this. I used to visit Senegal just for fun, and was in Bissau one time. I've walked into the impenetrable bush plenty of times with no plan, though always with a good map. You would fulfil my dream if you were to do this type of adventure in all the countries in the region. Senegal is objectively the best though, with no visa, unrest, or corruption to worry about.
Pic is a crocodile-infested water hole I found after walking across dried-up streambeds for a day and a half.