The one in your picture is a 737-800.

The Boeing 737 MAX have bigger engines, with a "sawtooth" pattern (engine chevrons) at the rear part of the engine nacelle. They also have different winglets, with spikes pointing up and down, and angled like this: >
The 737 MAX also have a different APU exhaust at the tail, which is long and pointy. The nose gear is also a bit longer. Try looking pictures of a Boeing 737-800 and a Boeing 737 MAX 8 and you'll spot the differences.

About the "8AS": the "AS" is the Boeing Customer Code of Ryanair.
For a long time, Boeing used to allocate customer codes to each of their clients. This means that if Ryanair order a Boeing 737-800, it would become a Boeing 737-8AS. But this is merely an internal code. The generic type is still a Boeing 737-800, probably no different from other Boeing 737-800s worldwide.
You can check out a list of Boeing Customer Codes here: https://en.wikipedi...