I am trying to do a kitbash and I have it edited how I want, now I need to export it I am using the ZE tools and was told I need to create a null and put my objects under it. I can't figure out how to do that and what I need to do afterwards. I am using softimage 7.5. Warning this is my first attemp at modeling so I am very nooby. Also if I missed a tutorial that covers this I am very sorry I tried searching but couldn't find anything on my specific issue.

I think, "put under Null", means, just draw your model, inside Null, like usual file, inside the folder.
It's cud be done, in XSI Explorer window. Just click Primitive>Null, and you create the Null. Then create or import some model, and put inside those Null. Model, realy will show up under Null, and it's call "hierarchy tree".

I already have the model but didn't start with a null can I add one now? I have three objects in my model a head, a body, and a jet pack. "and put inside those Null. Model, really will show up under Null" how do I put null inside those?

No no no, it doesn't matter if you already created the model or not. What you're doing is you're making the model a child of the null. What you do is you press 8 to bring up the Explorer and literally drag and drop your model into the null like you would do to drag and drop files into a folder.

I tried to do that, but it keeps saying command was cancelled in yellow at the bottom.

The yellow warning, usualy happens, if you do something wrong, like try put model under Null, when it already there.

Ummm I can't move the model under null, because it gives me the error it refuses to move the chunks under null.

EDIT after repeatedly trying to move them under the null it finally worked. and I then proceeded to export which worked fine I checked the model in swbfviewer and it looked like this From looking at the model it looks like its the sv sticking through. What would cause this issue?

Probably, you need to hide shadow model.
Click right mouse button on it, choose Properties>Viewing and uncheck View Visibility and Render Visibility.

You can also select the object and press H.

Ok that works now. I tried putting it ingame and that worked fine except it was like the jetpack was not attached to him, he moved but the jetpack was like static, and there was a blackish shape by his feet.

It seems, your jetpack, need to be Enveloped, to some bone.
You need to change purple Model theme, to green Animate theme. Select jetpack model, click Envelope>Set Envelope>Yes, and click bone Null, then click right mouse button.
I guess, black underfeet bug, may happens, if you try set nomal model, as lowrez, but not sure, if that correct for SWBF2.

Is bone null the null I previously created? Because I thought jetpacks were enveloped to the ribcage?

EDIT I enveloped it to the null I made but it still sticks the air and follows me.

Yes, you need to envelop it, to bone_ribcage Null. Not the main Null.

Ok how do I select that null I can't tell in the viewer exactly where it's at.
EDIT never mind I didn't know I could envelope after pressing 8, I thought I had to find the bone in the viewer.