How To NOT Act On Thoughts?

I am here for a month now and want to lose 40 pounds.
I watched all the videos related to SO course as well as the Urge Jar course.

I only came as far as noticing the urging thoughts I have and I have been obeying them and fulfilling the desire to overeat.

The skill I am lacking is the ability to watch my thoughts and not act upon them.
I don’t understand how is it possible to hear ever increasing thoughts that urge me to eat and not act.

I notice that I am having the thoughts. I recognize that if I act upon them I will stay overweight and will likely also feel shame later that day, but I cannot seem to watch the thoughts and just let them be.

How do you suggest I practice this? I have been trying every day to not follow them but I always do.