This was an animated film I had seen on TV when I was young. It was about a boy who lived alone on a planet (like the King Kai planet depicted in DBZ) that only had a house with two walls, a floor, and no roof with just a bed and stove. I vividly remember scenes of him making tea and him running then falling over hurting his knee.
He then leaves the planet by capturing a shooting star with a net, riding it through space (while a voiceover narration plays) until he arrives on a desert land and meets a moustached man who is a pilot whose plane has broken down in the desert. Another scene I recall is a sandstorm happens there and the pilot covers him and the boy with a blanket.
Sounds like a version of The Little Prince
It does sound like The Little Prince. I used to watch the 70’s cartoon version.
Here’s the trailer from the 1974 movie - https://www.youtube.com/watch?v=B8w0iRQDAl8I hope this helps.
It was actually two episodes of the TV series The Adventures of the Little Prince (Hoshi no Ojisama Puchi Puransu) in english dub.
https://www.youtube.com/watch?v=gx6Hcn5JRm4
https://www.youtube.com/watch?v=MzIVQTG--sA