Erythritol belongs to the polyol, or sugar alcohol, category of sweeteners. The product information notes that larger amounts may not suit everyone, so it is sensible to begin with moderate portions, particularly if you have not used erythritol before or you know your digestion is sensitive. This is most relevant when adding it to several foods and drinks on the same day, because the total amount can increase quickly without noticing.
A practical way to start is to use a small amount in one familiar item, such as tea, coffee, porridge or yoghurt, and see how you feel before using it in desserts or baking. If it suits you, you can gradually adjust the quantity to your preferred sweetness. If you notice discomfort, reduce the amount or use it less frequently; tolerance to polyols varies from person to person.
It may also help to avoid making your first use a large homemade dessert where the serving size is hard to estimate. Testing erythritol in simple foods first gives you a clearer idea of both the taste and how your body responds. Keep the product dry and closed between uses, as you would with other crystalline sweeteners, to help maintain its texture.