Question

Alguém pode me dizer se está frase está no presente perfeito.

"do not throw away what can be reused, keep in mind the salvation of our planet.
Save our planet!"

Answer 1

No, it isn't.

The present perfect is formed by the construction verb to have (have/has) + past participle of the main verb, and it's used to denote actions which either ceased recently or began in the past and perdure thus far. Examples:

I) They have lost the game (lost recently);

II) Paul has gotten good grades at school (and keeps on getting them until the present moment)