The first sentence doesn't work at all.
The second sentence is possible in theory but doesn't sound very natural (The infinitive use in the first verb gives a formal, slightly old-fashioned feel to the sentence.)
Better might be,
'Keeping early hours allows us to be happy.'
Though maybe you've heard of the English proverb, 'Early to bed and early to rise makes a man healthy, wealthy and wise.'
Student or Learner