Brother this situation is reversible.
These stages will be followed
1) Wash with strip shampoo
2) clay the car
3)chemically decontaminate the car
4)wet sanding starting from 1000-3000 grit
5) 2 stage paint correction (Compound, micro cut polish)
6) you have to apply a good coating or ppf
Though your car will be like new after this treatment but this will be temporary as the layer of oxidised clear coat will be removed and bare paint will be exposed to environmental damage
In this case ppf or a quality coating can save you
You can even do a diy at home