Can someone explain how you do "meuilleur , mieux"

Exemple :Ce gâteau est bon mais celui ci est meilleur.
Exemple : Kate est une bonne élève mais Mary est meilleure.
(This cake is good but this one is better.
Kate is a good student but mary is better.)

MEILLEUR : (adjectif) " MEILLEUR " est le comparatif de supériorité de " bon ". " Le meilleur " est le superlatif de "bon".
(BEST: (adjective) "BEST" is the comparative superiority of "good". "Best" is the superlative of "good".
MIEUX : (adverbe) " MIEUX " est le comparatif de supériorité de " bien ". " Le mieux " est le superlatif de " bien ".
(BETTER: (adverb) "BEST" is the comparative superiority of "good". "Best" is the superlative of "good".)

Cette voiture roule bien mais celle-ci roule mieux.
Ce modèle est bien mais celui-ci est meilleur.
(This car drives well but it runs better.
This model is good but this one is best .)

In English:
"Good" is an adjective and describes nouns. (usually after linking verbs)
"Well" is an adverb and describes verbs. (usually after action verbs)
I'm good at soccer, so I did well.

Likewise, in French:
"Bon" is an adjective and describes nouns. (also after linking verbs)
"Bien" is an adverb and describes verbs. (also after action verbs)
Je suis bon en soccer, alors j'ai fait bien.

The difference between English and French comes in when you try to do comparative and superlative forms.

In English:
Comparative: I'm better at soccer, so I did better.
Superlative: I'm the best at soccer, so I did the best.

In French:
Comparative: Je suis meilleur en soccer, alors j'ai fait mieux.
Superlative: Je suis le meilleur en soccer, alors j'ai fait le mieux.

(sorry if those sample sentences were a bit redundant)

Note that in French, adjectives change to fit what they modify.
Add an e to meilleur if the noun is feminine, and an s if it's plural.
For the superlative form, you also have to change the article (le/la/les)
Je suis meilleure en natation, alors j'ai fait mieux.
Je suis la meilleure en natation, alors j'ai fait le mieux.
Since adverbs modify verbs, which have no gender, they don't change.

There are also words reflecting the English words bad, worse, and worst:
mauvais, pire, le pire
(Though you can also just say mauvais, plus mauvais, le plus mauvais.
As for the adverb "poor," there is mal, plus mal, and le plus mal.
Both of these are examples of regular comparative and superlative forms.
Bon, bien, and mauvais are the only irregular ones.)

French is spoken in the city of hanoi which is in the north part of vietnam (middle).

Bonjor i believe thats how its spelled?