Treat this one a a mulligan.
Every build is a learning experience, so if you get another 'cuda' you will know how not to make the same mistrakes, but you will maker other 'learning opportunities'
In my experience painting planes & cars with a gloss finish is the hardest painting technique for me, your milage may vary.
Now you have a MULE, a target to practice on. Watch [only] a couple of YouTube videos on basics of painting cars.
Read and ask specific questions in the appropriate cars/painting forums.
Get comfortable with spraying food colouring or water soluable inks, use kids colouring-in books to practice in.
Get comfortable with cleaning the airbrush.
Clamp/mount your mule on a block so you can handle/move it without touching it.
Get some Badger StyNylRes, or MIG one-Shot, (is the same).
Shake it like you are at the disco & don't thin, you need a higher pressure than usual for eg acrylics to spray primer.
The gloss black, sands/pinks are easiest to spray, then the darker greys, with the pale grey and white are thickest.
Once you are comfortable with the above steps:
There are dozens of paint brands, so it depends on what you can get local to you.
To start with, always use the branded thinner for the paint.
There are those that say use Dollar/Hardware store slosh paint around and to thin & clean with.
These can save you a few dollars at the cost of buying a (modelling) lifetime supply and introducing a huge heap of other variables, keep it simple to start with, (as in: anthing with a hint of alcohol/IPA in it will turn Vallejo into instant rubber goo!)
Get some Tamiya Gloss acrylic or lacquer in your colour choice.
Stir very well.
Transfer enough into a seperate lidded container, 35mm film can, graduated measure cup, etc.
Thin the Tamiya acrylic or lacquer paint with Tamiya Pink Top LACQUER thinner, add 25% ratio (3 drops paint, 1 drop thinner) stir & drip, add a few drops of thinner, untill you are happy with how it flows.
Tamiya likes 25%-35% thinner depending on the paint, humidity, heat, time of day, how much hurry you are in, if SWIMBO has got a 'honey-do' list on the go...
Other paints have slightly different ratios.
Let Us Spray.
If you don't like you spray job, dump the whole thing in IPA or appropriate, strip back, clean up & start again.
If the above sounds like a lot, it is only small steps, & practice takes time, Sadly skill & experience isn't included in the box!