It is best to use a GPU when playing a game or doing video editing. However, integrated graphics on your CPU will still work in a pinch.

If your PC is using integrated graphics instead of GPU, first of all, check all your cables, force programs to use dedicated GPU, and check this post.

Nvidia's tech eases the workload of its RTX graphics cards, so will a budget or older CPU bottleneck performance?

If you have a dedicated Graphics Card or GPU, you can force a game to use it instead of Integrated Graphics, using one of these two methods.

While testing Halo Wars Definitive Edition on my Surface Book, I noticed that it wasn't using the powerful discrete NVIDIA GPU, defaulting instead to the integrated graphics.