One thing I’ve learned is goal setting is that you have to be specific. (And this pertains to any aspect of life but I am applying it to nutrition here.) If your goal is just to “eat better” like you hear all the time you have set yourself up for failure. If you want to improve your diet you have to define specific goals and educate yourself on what you have to do to achieve that specific goal. Then you know what you can and can’t eat or how much, etc.
But, don’t wait until you think you’ve learned enough. Get started with what you think you know and reevaluate and improve on your plan as you go. Some of the best lessons I’ve learned in nutrition came from what I was doing wrong (and still are.)
If you walk into a store looking for “better” food you will be basing what you purchase off marketing techniques and will get nowhere. Find some sort of resource to start with. I personally was recommended to check out The Food Babe which is an awesome source but you can find plenty for yourself that fits with the specific goals you have in mind. There are countless blogs, podcasts, and probably millions of hours of good content available for nutrition related information.
When shopping define what you are looking for. Be specific! Go in armed with this as a baseline for what you end up with in your cart. I know if I walk into the grocery store without a plan I get to the checkout thinking what is all this crap? Make rules like; “nothing with over 8g of sugar” or “only whole gain bread products”
I set rules for myself in and out of the store as well that are in line with my goals. A few for an example are: 1) If I need to eat “fast food I can go to x,y,z. 2) No white bread. 3)Nothing with the ingredients a,b,c. These are just a few examples to show you the idea. I am no food expert. What I am an expert at is defining goals and sticking to a plan.
I hope this helps you to go out and create the plan you need to succeed in your own change.