Every thing you eat affects your blood sugar levels. The only way to find out what you can and cannot safely eat is to test before and 2 hours after you eat something, or a meal. You need to write down what you eat, and the quantities too so you can see what, if anything, is spiking your sugars or reducing your sugars.
It is a pain, I know, but if isnt forever as you will soon get a feel for your favourite foods and meals and be able to work with your knowledge.
People on here are happy to advise you when you have some data eg. posting a meal and your bs results. They will look at it for you and help you find out how to tweak it for the best result for you.