Sadly standard wheat based flour is almost entirely carbohydrate making almost all mainstream baked goods a no no when living a low carb diet.

Also sadly, replacing standard flours with a single low carb ingredient (like Almond flour) is also not that simple as the constituents of these alternatives differ greatly from traditional flours, so finding a balance is required.

Almond Flour is probably one of the the best and most versatile of the alternative flours. It's high in fat and low in gluten so is great for keto. But that also means that your bake may lack structure after baking so you might need to counteract that with some egg, aqua faba (for the vegans) and bicarb.

A much more in depth overview of the topic can be found here at:- Keto Flour Substitutions