There's nothing wrong, the A12-9720P is a 15w SoC, it's not intended for heavy gaming.
If I recall correctly AutoCAD is heavily dependent on CPU performance, not GPU. The 5400RPM hard drive that accompanies 9720p-equipped laptops is a significant bottleneck when loading textures.
An APU like the 9720p does not have low latency onboard VRAM, rather it has to share the comparatively high-latency system RAM between its CPU and GPU components. This will significantly slow down system performance in graphics-intensive applications such as games. Even if your laptop comes with dual graphics, its graphics performance is not going to be reaching the level of an entry-level discrete GPU like the RX 540.
Sorry, but the guy in the store definitely lied to you. Modern games demand very high-specced laptops to even play smoothly at medium settings with 1080p.