You have some issues where your meshes are joining up, especially the windscreens. I think there are a few tutorials about which show a car modelling process that overcomes that, but adding loop cuts and creasing edges slightly with shift-e will help.
Tyres and the headlight area need more work, there are a few tyre tutorials about, also I would put a plane or a basic box shape behind the grill with a dark material to stop the viewer from knowing that it is an empty shell.
Some materials on the car could do with a little tweaking, the studio set up with the grey is quite nice though.
I hope some of that helps, you’ve made a good start but you just need to do a little more work.
The workflow Is very similar in most apps. I used to check out a site call scratch made cars which had some very useful resources, they email you though if you don’t visit the site for a while, which I find mildly irritating.