“Canola” was a word made up a couple decades ago to refer to “Canada-Oil” (Can-ola)and the oil is from rapeseed. They didn’t like the sound of “rape” (though it comes from the Latin word “rapum” meaning turnip.) The rapeseed is related to mustard and turnip -— not sunflower: it’s a brassica, also related to cabbage, collards and such.
That makes it sound OK. What could be bad about cabbage etc. ; )
It’s all pretty nasty stuff. They crush the seeds and then use a solvent to extract the oils, then steam off the solvent. Then they use lye (i.e. sodium hydroxide) to remove some of the bitter-tasting acids. Canola was bred from rapeseed, it is not exactly rapeseed. The reason I said sunflower is because sunflower is a seed and a closer match than soybean. An expeller-pressed oil (sunflower or canola) will be edible, perhaps odd-tasting, but probably healthy. Expeller-pressed soybean oil is nasty and has to be processed which is probably unhealhier but neutral tasting.