No, it would not be that. Read what I said above: "importa" is the conjugated form of "importar," meaning he/she/it matters. "No importa" = He/she/it does not matter. "No es importa" doesn't make any sense, because "importa" is already a conjugated verb - "es" is not required there. If you want to say "it is not important," you could say "no es importante." Importa and importante are a verb and noun, respectively.