A toaster can work with both pre-sliced bread and normal sliced bread. In fact, toasters are designed to toast regular sliced bread, and they can accommodate different thicknesses of bread slices. Pre-sliced bread is just one form of sliced bread that is convenient for people who prefer uniform slices.
The confusion might arise from the fact that some older or more basic toaster models have smaller slots, which may not be wide enough to fit very thick or large slices of artisanal bread or homemade bread. In such cases, people might assume that the toaster only works with pre-sliced bread.
However, modern toasters typically have adjustable slots that can accommodate a variety of bread sizes and thicknesses. Many toasters also come with wider slots to fit bagels, thicker bread, and other specialty baked goods.
If you're using a regular, modern toaster, you should have no problem using normal sliced bread or even slicing your own bread for toasting. If you encounter difficulties fitting your preferred bread slices into the toaster, you may want to consider investing in a toaster with wider slots or an adjustable setting.