The use of cong(从) and dao(到), is the "formula" you employ express from one time to another in mandarin.
从 + Time 1 + 到 + Time 2.
Hopefully this explanation is helpful to someone.
Is it wrong to say 从十二点到一点老师吃饭? If it is, why? Any specific rule?
It is correct, and it is accepted now.
Is there a way to know if its one in the afternoon like 1pm or 13:00?
wrote 老师吃饭从十二点到一点, is it wrong? Should 吃饭 only come at the end?
That is incorrect word order. The time has to come before the verb in Chinese.
Thanks man.
从 (cóng) = from/to follow 到 (dào) = to (a place)/until (a time)/to arrive