All depends on your budget.
For scratches there's no magical product, though the most commonly used is formula 1 scratch out which basically does not removes any scratches but hide them temporarily.
Other than that there are superior quality products but prices might be very high.. such as Meguiars ScratchX 2.0 its price is around 2000 Rs I guess.
However non of these products work on deep scratches where base coat becomes visible, for such deep scratches sand paper is the only solution.
There no polish for tires, only gels and spray waxes.
7CF would do good enough however you can use formula 1 protectant too. Or if you wona buy quality then go for mothers or meguiars brands.
For polishing chrome parts you can use entry level kiwi bras polish or you can use Turtle chrome and metal polish.
Remember a polish only polishes, wax is to protect.
Hence use polishes prior to waxing.