i am a complete beginner when it comes to houdini so bare with me.
i am trying to put a smoke simulation on an alembic sphere using the scatter points method, and the reason its alembic is because i first had it in blender and exported to houdini, (i did this because i animated in blender and baked the animation.) now i am trying to put a smoke simulation thing (so smoke comes off of it) and not only is it completely black its also cut in half and i have no idea why ):

A little hard to tell exactly without a hip file. But I'd guess that the half sphere has something to do with your sphere setup. The alembic you are bringing in defaults to a packed alembic. Instead of loading it as individual points and prims, it gets loaded as a single primitive per object. This helps speed load and playback times, but it means that when houdini looks at it, it doesn't really see a sphere it sees (likely) a single point.

Then you're piping that into a sphere node, which uses its input to set bounding regions. It may be that since it's not reading a full sphere out of the alembic node, it's not creating a proper sphere with the sphere node.

Instead, after the alembic node append a convert node and set it to convert to "polygons". The pipe that directly into the scatter node.

And lastly I'm guessing the smoking isn't rising is because in addition to setting a density attribute, you also need to set a temperature attribute before you rasterize the attributes. No temperature, and there's nothing to drive the movement of the smoke.

Post a hip file if it's still not working.

right it doesn't seem to be working correctly so here's the hip file (i aint 100% sure if this is how you're meant to send it, hopefully i sent it correctly)
it still cut in half, i kinda fixed the simulation but its somehow floating the wrong way.