"I've grown a lot emotionally, and I realize the importance of meditation"

I've accumulated stress over the years, and even though I look well, my BP has been mostly high for the last 8 years. I mean, I've always been slim, never smoked, low sugar diet, often on my feet walking here and there at my job as a nurse. 
I refuse to take hypertension meds because they don't treat the problem and actually cause subtle harm. I've tried "everything" including raw beet juice, raw garlic, no pork... 
Nowadays I'm taking adequate water (Zero water) with liquid magnesium throughout the day, DHA, ketogenic diet with intermittent fasting, arginine, fresh lemon juice, nitric oxide-producing probiotics. I've been using the ReSPIRATE gizmo for a couple of months, but BP still high. I believed it would work, being that it's like meditating on your breath. I will continue with it, though. 
So far, I've been mostly treating the body. What about my mind? I'm convinced that I have high cortisol levels due to accumulated stress throughout my years of people-pleasing, and lack of self-love. 
I've grown a lot emotionally, and I realize the importance of meditation, but I don't know how. Now I decided to invest in myself, and take this M Word Quest.