The lower the fat, the higher the carb. Ignore the glycaemic index, it’s complicated.
Dump carbs, vegetable and seed oils and eat protein, dairy, sat fats, above ground veg, berries, nuts and seeds. Test your blood and most important of all, stop eating sugary stuff, it will kill you. Hummus is better than crisps.
Search the forums, there are tens of thousands of threads and posts about LCHF.
People will think I'm paid to promote Jenny Ruhl's books, but sadly, no! She has written a whole book on losing weight by/while lowering your bg, which is something she herself, a long-term diabetic, has had to do and struggled with. I really think she has the answers you need to your very natural confusion: https://www.amazon.co.uk/Diet-101-T...1515670158&sr=1-4&refinements=p_27:jenny+ruhl
You can also find lots of info.on this problem for free on this page of her website: http://www.phlaunt.com/diabetes/sp3index.php