Bai Shou Zong Dong Yuan: Konglong Yongshi Dang An

This series tells the sci-fi story of three friends who grow up alongside alien dragons and protect their home. The protagonists, Long Xingzai, Xiaomili, and Siyanzai, are best friends living on Dinosaur Island. One day, Long Xingzai encounters a mysterious spaceship. This enigmatic spaceship belongs to the dragons of Dinosaur Planet: Flame Beast, Lightning Beast, and Rock Beast. It turns out that Dinosaur Planet has been destroyed by the villainous Shadow Captain, and to save their home, the dragons decide to travel to Earth to find new dinosaur warriors. By chance, Long Xingzai becomes a dinosaur warrior protecting the universe! Can they overcome the numerous difficulties and challenges? The exciting adventure has begun, go for it, young warriors!

(Source: Douban, translated)