You cannot stop the mind from thinking, for it is the job of the mind to think!
The mind is just like the other senses, like the ears hear, the eyes see, similarly the mind thinks. The mind keeps on performing its function (duty).

So, the thoughts will continue to flow, no matter how much you try to stop them. Stopping the mind from thinking will actually lead to an absent mind, we don’t want that, right?
The mind is like a radar!

What is the mind like? It works like radar. Just as there are radars that tell us that three planes are coming this way. At that time, the person seeing the radar does not get frightened. Things seen on the radar are not meant to frighten anyone. They are there to alert us! So we see what comes up on the radar, we do not try to stop it. If something is not appropriate, we communicate and help the plane change the direction.

This is how you have to converse with your mind and put it to good use. Its nature is like radar. So, when it sees something that makes one anxious close to it, it shouts out. Just as the radar alerts, here the mind alerts you. It will say, ‘Hey, this plane is coming from behind.’ And you say, ‘Noted, I am turning it around.’ So, the mind helps, it warns us just like the radar.

The mind never holds on to a single topic. It is the person who holds on and experiences suffering. One becomes frightened, fearful and even worried and then the mind does not move away from that particular topic. Once you explain to it, it will not get frightened. And it will move on to another thought!

The mind and Real you!
The mind is separate and you are separate. To become one with thoughts is because of illusion.
You become one with them because of the false projection that, ‘I am the body and this is my thoughts’. Once you realize who you really are, then in the awareness of the Self (the real Self), you can remain separate as the ‘knower’ and the ‘seer’ of every function of the body - thinking, speaking, acting.

Through the attainment of Self-realisation, the fear or concern about ‘what does the future hold for me’ will also disappear. This is because you then come into the true nature of the Self. You are no longer the owner of the mind, but rather a mere observer and knower of each thought! With the knowledge of the Self, One always remains in the present and never fears the future or is concerned about the past.
Thus, to conclude…

The mind is tasked to think, and the thoughts can be either good or bad. When external events and inner circumstances arise, which are dependent on space, time, karma etc. the thoughts in the mind sprout. These thoughts come and go. And our job is only to ‘see’ and ‘know’ every thought that the mind shows, every thought, the nature of which is to come and go. We have to see these thoughts without getting engrossed in any of them, meaning without becoming one with it; without experiencing fear, worry or stress!

When can the interference of becoming one with the thought cease? It is when the Enlightened being (Gnani Purush) bestows the knowledge of the Soul upon us by gracing us with Self-Realization that one ceases to become one with everything that takes place within and without.

To know more: https://www.dadabhagwan.org/path-to-happiness/spiritual-science/know-the...

Author's Bio: 

Ambalal M. Patel was a civil contractor by profession. In June 1958, spontaneous Self-Realization occurred within Ambalal M. Patel. From this point on, Ambalal became a Gnani Purush, and the Lord that manifest within him became known as Dada Bhagwan. A Gnani Purush is One who has realized the Self and is able help others do the same. Param Pujya Dada Bhagwan used to go from town to town and country-to-country to give satsang (spiritual discourse) and impart the knowledge of the Self, as well as knowledge of harmonious worldly interactions to everyone who came to meet him. This spiritual science, known as Akram Vignan, is the step-less path to Self-realization