A version of the Cube can be seen in the Marvel Cinematic Universe, where it is known as the ''Tesseract''. It is first seen in Captain America: The First Avenger, where it is revealed that it was brought to Earth by Odin centuries ago. In the film, the Red Skull finds the Tesseract and uses its power to create weapons for Hydra before he is defeated by Captain America and the Tesseract is retrieved by Howard Stark. It is seen again in The Avengers, where it is stolen by Loki from S.H.I.E.L.D. Loki then uses it to create a portal to allow an invading army of Chitauri to attack the Earth, but they are defeated by the Avengers and the Tesseract is taken back to Asgard. From there, it is briefly mentioned in Thor: The Dark World and in Avengers: Age of Ultron, where it is revealed that the Tesseract contains the Space Stone, one of the six Infinity Stones that Thanos wishes to obtain. At the end of Thor: Ragnarok, Loki steals the Tesseract as the survivors flee Asgard to escape from Hela. At the start of Avengers: Infinity War, Loki hands the Tesseract over to Thanos to spare Thor's life. Thanos crushes the Cube in his hand, revealing the Space Stone within before placing it in his gauntlet.

Is it true that is the cosmic cube the same as the tesseract?
yes