bread flour strength?
"Strong flour" and "Bread flour" generally mean the same thing -- lots of gluten, so the dough can stretch and incorporate lots of bubbles.

Not all bread demands high-gluten flour, but the traditional airy loaf of Western Europe and most of the USA does.

If what you're making is bread of that kind, "strong bread flour" is what you want.

If you're making a cake or a sauce, things will probably be fine -- try it. It might not be perfect but it won't be a disaster. It's worth having some less strong flour (often labelled as "plain flour") in your store cupboard.