In English, adjectives may have three different positions. But, using any adjective at any position is not possible.
1) Attributive position - before noun. Most adjectives go before noun.
Green tree
Happy girl
2) Predicative position - after verbs.
The tree is green.
The girl is happy.
3.Postpositive - after nouns.
After certain nouns:
Two meters tall
Two kilometers wide
Some fixed expressions:
Court martial
Heir apparent
If there is an superlative adjective modifying noun, adjectives ending in -able / -ible may come after that noun.
worst choice imaginable
the best hotel available
Some adjectives can be used both at "attributive" or "predicative" position. E.g;
Happy girl
The girl is happy.
Some adjectives may have different meaning when used attributively and/or predicatively. E.g;
My friend is poor.
My poor friend
Robin Harris was late.
The late Robin Harris
Some adjectives, such as afraid, alive, alone can only be used at predicative position. E.g;
John is alone.