The Space Lab Creator Guide This contains lots of info and resources on creating your program. Below is a list of items picked out of it as a possible order to work through:

1. A good place to start is the tutorial on finding the speed using photos from 2022/23 including EXIF data
2. Next, do the tutorial on Getting Started with the Pi Camera
3. Now use the code you wrote in 1 and 2 to create a program that will use the camera on the Astro Pi to take a series of photos, then work out the speed from them. You can test this using the Astro Pi Replay Tool (a simulator that will make your program act roughly as if it is running on an Astro Pi on board the ISS)

After doing the three steps above you should have a program that will calculate the speed of the ISS using the camera on the Astro Pi on board. However, it may not be terribly accurate - can you improve it? As with any problem, there's also a possibility your program will misbehave during its run, and you definitely won't be on the ISS to sort it out! Is there a way to handle this?

To address these issues, look at the following:

Exception Catching

Improving the calculation