Get creative in racing games like NFS or Gran Turismo, but IRL leave the car stock, rather make sure all MOT advisories are sorted.
We've all been there, want to prove to everyone we're the best drivers on the streets, but there's a reasons why insurance is so high for young drivers.
You share the road with a lot of people, among them many families, so safety first, for them and you as well.
If you get more experience on the road, fact is even after 20 years you can learn new things, and still want to modify, take the car to a race track and have a blast there.