I'm completely new to this, is it as simple as this or quite complex
Well, that depends. It isn't putting somebody on the moon, but it isn't the BLINK sketch (do you know what that is?) either.
That sensor want I2C or SPI for communication, so you'd have to learn how to talk to it.
Who know what "display" means? A 2 line LCD perhaps? Have to learn to talk to that.
Have to learn a little programming.
Coefficient of friction for a blocking sled? Don't know what I'd do with that.
If you are wanting a self contained thing you can stick on the back of a blocking sled, you'll have to figure out a box and batteries and attaching parts so they don't fall off, etc.
It's involved.