I really can't word the basic concepts of how our thoughts affect us (CBT basics) better than this article. Please start here:
https://www.therapistaid.com/therapy-guide/cbt-psychoeducation
So, to summarize: our minds are little word machines that are constantly making (often unconscious) interpretations of the world around us. These interpretations are often filtered through our core beliefs, which are deeply held things we hold to be true about ourselves or the world (again, often subconsciously). We can also have thinking biases called cognitive distortions that have become patterned into our thinking over the years.
All of these thoughts/beliefs/interpretations affect how we feel. It is not the event itself that makes us feel something, it is our interpretations and thoughts about what happened that lead to our feelings. This is actually great news, because the only thing we have control over is ourselves- ultimately while we can influence and change things, we do not have control over others and the world at the end of the day. So if we want to change how we feel, we change how we think!
And when we change how we feel, we change how we act and behave. And if we start to show up in more calm and confident ways in our world, we’ve started a positive cycle.
Just a side note, we can also make positive changes in this cycle at the point of “behaviors;” change isn’t only possible in the “thoughts” areas (the emotions one is the point that is most impossible to just change- that’s why we need to change our thoughts and behaviors to feel better). As we engage in new behaviors: exercise, using coping skills, working on interpersonal skills to grow better friendships, finding activities that make us feel happy and peaceful and then doing them (gardening, reading, painting, getting a massage, etc), we can also start to feel better, which may make it easier to think more positive and effective thoughts, again making a positive cycle happen.
To finish up, I want to talk about self-talk. Self-talk is the words that we are saying to ourselves- it’s our internal dialogue. We can start out by just being mindful of our self-talk without changing it. Like said, what we say to ourselves is often under our consciousness radar. So a good start is to just start unearthing the things that we are saying to ourselves all the time. Then, let’s examine it- how is that self-talk working for you? Is it helping or hindering you reaching your therapy goals? And then, let’s change it if it’s not helpful to you feeling the way you want to feel and doing the things you want to be doing. I like to encourage clients to use positive, reality-based, and effective self-talk. We work on what that might look like for each individual together.