Change from student visa

I am currently a student visa holder here in japan, my aunt is married to a japanese and my uncle wants to sponsor my visa now. Is it possible to change the status of my visa? Thanks.

From student visa to which visa?

PS: There is no nephew visa.

And the status change will be from "student" to what status?

To working visa? My uncle run and owns a bakeshop so he wants me to try working there and later on study baking.

It doesn't work that way. It was already said: work visa does not exist . There are plenty of visa that allow foreigners to work like engineer visa, international services visa etc.

You live in Japan, you should know that, ever been at immigration office? You know the big building were foreigners get visa extensions and changes of status, you should try that place, they are often helpful.

PS: There is no baker visa.

your uncle is a Japanese. he can contact immigration office by himself in Japanese, because he needs to prepare documents to apply it.

I was wondering about that – if he has a business and wants to hire you as an employee there, and further if you qualify for that work resident status on your own, certainly he can sponsor you for that particular resident status.
There is no general gworkingh visa (by the way you donft call it gvisah once you are living in Japan; it is called gresident statush) but there are different kinds of employer-sponsored resident status according to the type of profession, with accompanying requirements. So do you have any chef/patisserie training or experience?