Help

The carpet can be simulated with scale car 'flocking' basically its a fine fluff that's glued to represent scale carpet.

Leather can be simulated with paint and proper gloss for the shine. To add real leather will be a lost cause as the seams will look 6 scale inches on a 1/24 scale auto. Experiment with paint, a high gloss can be painted on with future floor polish. Worn leather can be done with a semi gloss clear and highlights.

I sprayed a black leather jacket with a flat clear and used black & dark purple pencil crayons for semi

gloss highlights.

I've builded 3 models all planes this is my first car I wasn't really looking to scratch building it but I was hoping to add stuff like leather seats and tires and so forth. I was planning on useing a kit but there are going to be points where I skip a direction and add something eels from a different kit. It's going to take a while to make my basic question is if anyone has any ideas on how to make like adding carpit inside making my own seats with leather and so forth. But still thanks for the answers

Unless you are a very experienced modeler, I would NOT scratchbuild a Nova.  I believe there are several kits of Novas available (maybe out of production but they should still be available).

I haven't built any cars in a long time but I'll tell you what I can and maybe it will help. Without knowing what particular Nova you are looking for all I can say is look at Revell or AMT for Nova kits. I have seen Nova kits recently but I don't recall what year Nova they were because I just glanced over them. As far as detailing goes you can check the Detail Master and The Model Car Garage websites. They both specialize in aftermarket details for super detailing model cars. They also carry other accessories for building and detailing model cars. If you have a local hobby shop you can probably get them to order what you need. You can also check Scale Auto Magazine...a sister publication to FSM...for tips and ideas on completing your project. One more thing, and I don't know why I didn't mention this before, but you might want to head over to the Model Car forum on here before you follow all my other suggestions. Someone on there can probably steer you in exactly the right direction you need to go. Just be sure to tell them in more detail what it is you want to build. Hope I was able to help you. Good luck!