Education that didn't take place
Guys, I really need your help.
How to say that a person is not well-educated by using the noun "education"?
poor education?bad education? insufficient?what ajective would be the best variant?

Question

Answer

He is uneducated.

Answer

Using "education":
- I lack education. 
- Your education is lacking / poor / insufficient.

Using "educated":
- He's uneducated.
- She isn't well-educated.
- We aren't highly-educated
- They're poorly educated.
- I am ill-educated (archaic)

Answer

Adjectives you could possibly use to refer to a 'poor education ' using the word EDUCATION :

- Ineducate education
- Substandard education
- Below-average education
- Deficient education
- Inferior education
- Low education ( lower education levels)

Answer

"He did not have much education" is the one expression most likely to be used by native speakers if and when required to play according to your specifications.

Answer

In addition to John's terrific answers:  his/her education is rather sparse; 
                                                                    their education leaves something to be desired.