Keto is about reducing carbs. Sugar is pure carbs. Sugar needs to be removed.
But I like food to taste sweet.
There are tricks to make your palate believe it's sweet: Sweeteners
As a result they don't increase blood sugar levels* and are keto-friendly.
* apart from Sorbitol, Xylitol and Maltitol that do!
Artificial Sweeteners are chemically-engineered powders that trigger the same palate response as sugar
They are technically keto-friendly but they are suspected of adverse side-effects.
And their high sweetness make them impossible to use in baking or cooking.
Natural Sweeteners are chemically extracted from natural ingredients.
Some like Monk Fruit or Stevia have a very high sweetening power and are generally sold in blends, mostly with Erythritol.
Others like Tagatose and Allulose are similar to glucose but aren't digested by the body, making them keto.
Easiest to use when blended (1:1), but slight grassy taste
Easy to use, safe, 0 carbs
Easiest to use when blended (1:1), no aftertaste