Dear Phu Du,
You raised a question with English words. Hence, it could be better to consider this issue in English language. To start with, there are two thing we need to consider prudently: Terminological and philosophical aspects.
1. Terminological speaking:
Education is a process of teaching, training and learning, especially in schools, colleges or universities, to improve knowledge and develop skills. (Oxford Dictionary)
Indoctrination is the act or process of forcing somebody to accept a particular belief or set of beliefs and not allowing them to consider any others. (Oxford Dictionary)
It can be seen that the main difference between two definitions is about the freedom and willingness in the two processes.
Education aims to general knowledge which is commonly and universally accepted. In a good educational system, teachers or educators usually encourage two-ways in teaching. In other words, students can raise any question to challange their teachers and vice versa. As a result, creativity and development should be the fruits of education.
In contrast, indoctrination has no room for freedom, discussions, challenges, two-ways of teaching or differences. Thus, it only focuses on forcing and forcing following one way and one understanding.
The bottom line is the context of society where education is following its original definition or not! In a dictatorship society, education could be an effective method to support political system. That is why you can see education and indoctrination intertwined with each other. Differently, a society which democracy and human rights are considered seriously, the system of education will support human freedom and development; and at the same time, eliminate indoctrination.
2. Philosophically speaking:
It is interesting to see this issue in the lens of philosophy.
Only human beings can think deeper and communicate in sophisticated and complex language. This special ability bring human beings to the best level of civilization on earth.
It can be seen that, every political system, to some extent, will add something so-called "indoctrination" to support and protect its structure. However, as mentioned previously, the ability to think of human beings enlightens something wrong, something needs to change, something needs to improve. Looking at this point, indoctrination becomes the source of real education to produce new and better things eventually.
In short, thank you for this question.
Hopefully, the writing can give you some ideas to sleep on it.
I open for any further discussion about this.
Have a nice week,
God bless,
With love,
Happypencil