I want to work with BlackPill STM32F411CE using Keil uVision 5. Unfortunately, Keil is not able to compile program simply because it doesn't recognize STM32F4 family for some reason. Here are the steps I took:
First I downloaded necessary packs needed using Pack Installer:

After installation, F4 family is not present inside Options for Target > Device:

Therefore, Keil is not able to compile code, and gives this error:

