Do I need a degree to get a work visa?

So I have been doing a ton of research because after high school, I want to go study Japanese voice acting/becoming a seiyu. I would get a student visa for that but, after I graduate I want to work as a seiyu but I would need a work visa, specifically an entertainer work visa. Would the vocational school be enough to get a work visa or do I still need the bachelor's degree? This question isn't really can I get a job in this field, it's more of legally, can I get a work visa in this field.

entertainer work visa: this is for professionals who already established their positions in their fields as entertainer. you are not eligible.

according to some web sites, there is no working visa category which fits to seikyu.

Generally speaking, those graduating from a vocational school are able to obtain work visa/resident status if they find an employment/job in the field they studied in.
However, you need an employer (= sponsor for the visa/resident status), and I find it unlikely that a voice actor/actress-to-be just finishing a vocational school, no experience, would find an employer right away for a full-time (or sufficiently paying, in any case) position with visa sponsorship.

some website says that there is no work category to fit seiyu, after you graduate vocational school.
例えば、美容、アニメ、声優などの分野には該当する在留資格がないことによるものです。

Okay, so what I have gathered is:

a) I am not qualified/entertainment visa is for people that already are experienced in the business (i.e. well known singers).

b) even if I can get the vocational degree, I need a sponsor and that's highly unlikely because I just graduated with no experience.

Thank you to everyone that answered, but now I have a couple other questions: If I got a bachelor's degree in voice acting, etc. would that help me get a work visa in that industry? Are there any other majors that I could get a bachelor's degree for that would help me get into the seiyu industry? What work visa would I need exactly?

Please read the above posts carefully.

There is no work visa category for which you can apply with the job of “voice actor/actress.”

Also, please note that a degree (regardless of whether it is from a vocational school or a university) does not automatically get you a work visa; to apply for a work visa, you need an employer-to-be (= sponsor) making you a job offer.

So at this point, could I even get a work visa for this industry? If I can't, do you know any alternatives that are similar that I could do?