On the second one you need to change 'consist' to 'consists.' You need to use 'on' instead of 'in' also when you say "A human is the best driver in the "selfishness" road. You need to say 'accounts' instead of 'account' on the last one. You may want to say 'the best' instead of 'best' as well. It's not wrong, it just makes more sense. But everything else is perfect. :)

The way I've started learning is by getting a handful of verbs, a handful of nouns, and a handful of adjectives. Now find the simplest way to combine them into a sentence. If you get ten each, memorize those, and can piece them all together easily, you've just made around a thousand sentences. Then get more complex from there.

Yes. :) You want to put 'the' before 'questioner.'

The sentence is confusing. You want to show who is being accompanied in the first part ('With the right one accompanying'). You want to say 'feel' instead of 'felt' because you are using a future tense. A possible translation would be: 'With the right one accompanying you, whatever the road, however long, however awful, it will make you feel like the road is short!"