Simulation games are fun and relaxing to play, and often a good tool to learn concepts and gain experience ready for doing the real thing. They can be used with just a keyboard or a games controller, but to get real immersion you need to add peripheral devices such as a steering wheel, foot pedals, gear shifters etc.
Dashboards within the simulation game are often very small and difficult to see, especially when on a smaller screen, so the use of additional devices to display this vital information also helps a lot.
And anyone who has tried to play complex video games or simulators just using a keyboard will know, trying to remember the dozens of complicated key combinations and which keys do what, can make or break a good game and spoil the enjoyment when wrong keys are pressed in a hurry. So external 'Button Boxes' that have easily identified and dedicated buttons and switches, can take the playability to a whole new level.
Below I will show some of these devices, and attempt to highlight both the good points and bad.
I can only recommend what I have actually tried out and used myself, and will point you towards suppliers that I have actual experience of purchasing from. Therefore there will be other alternatives!