fuck me i just wrote a big reply and lost it.
it's a sachs westlake (or sundancer, theres a few versions of that frame) with a 504/1a motor that looks like they swapped a D cylinder and piston onto, and then made that janky ass intake to a dellorto PHVA carb. That carb can totally work on there but isnt original, it came on bikes with oil injection and the little brass nipple on the side is where the oil would have pumped in to mix with the gas going in - you will need to cap that nipple off or it'll make an airleak and not run right.
Wiring, search the wiki for sachs wiring diagrams, it should match this one: https://www.mopedarmy.com/wiki/File:Westlake.gif
Should be 4 wires from that stator: Yellow, Green, Blue and Blue/black (or green/black)
To get it to run, easiest is run blue directly to the ignition coil and ground the green and the green/black. That'd make the brakelight not work, but omits a common issue where it wont spark when the brakelight is blown. Yellow is lights, you can worry about that later once it's running. If it still doesnt spark, clean the points.
Read through Fred's guide - it's an excellent troubleshooting wlakthrough that covers about 99% of your possible issues and how to fix them.