DNS Problems

[new new]

i was reading and i found out that i needed another ip to for my DNS to work i dont know if its true or not so i bought one.

i did a DNS report on my domain and got 4 errors,

1.Open DNS servers
2.No NS A records at nameservers
3.Number of nameservers
4.Single Point of Failure

can you please help me out with this please any help will do.
thank you