Question

esse texto ta certo?
This is a kangaroo it´s exotic, from Australia, it is mammal and marsupial and big and small. It´s cute. The kangaroo is brown and it lives in the forest

Answer 1

Não tá certo, não. 
This is an exotic kangaroo, it's from Australia. It's mammal, marsupial and big/small (ou um ou outro, senão vai ficar "ele é grande e pequeno"). It's cute. The kangaroo is brown and lives in the forest.

Assim fica melhor.