Why Aren't There More People Learning Tanach?

Source Sheet (RabbiKraz.com/Tanach)
• Is one allowed to teach if he does not know Tanach?
• What does the Mitzvah of Yedias Hatorah entail?
• The Efodi explains the importance of Tanach.
• Is one allowed to learn Tanach by heart? What about at night?
• What did Rashi mean when he wrote Makas Bechoros is equal to all of the Makos?