F1 2021 is a graphics-oriented game, therefore you must have a high-end PC to run it without any problem. However, if your system doesn't matter with the minimum, you will face different difficulties including the loading screen issue. Below are the minimum requirements to run F1 2021 with ease.
OS: Windows 10 64-bit or later
Processor: Intel Core i3-2130 or AMD FX 4300
RAM: 8 GB RAM
Graphics: NVIDIA GTX 950 or AMD R9 280
DirectX: DirectX 12
Free Space: 80 GB of space