People who are not a permanent resident or national of one of the EU / EEA countries, will need work permit /visa sponsorship in order to be employed in The Netherlands. This will unfortunately make the job search much harder, since many companies are not willing or able to offer this sponsorship. Even if a company is approved and acknowledged to be able to offer sponsorship, they will only offer it for highly skilled, experienced technical specialists such as software or electronics engineers, and possible for higher management roles. Hence, this sponsorship scheme is called the Highly Skilled Migrant scheme. Anyone who has a different background/profile and would need sponsorship, has in reality basically no chance to find employment in The Netherlands.
The sponsorship is always job- and company-specific, there is no such thing as a general work permit that allows being employed by any company in The Netherlands. The so-called European Blue Card is often considered an easy entry on the Dutch job market, but is practically of no use most often, as there are still criteria that apply that make this a basically unattractive and difficult option for Dutch employers. Here you can find more information: https://ind.nl/en/residence-permits/work/highly-skilled-migrant
Please be advised that agencies can not offer the work permit, only direct employers can. If any agency informs you that they can arrange work permit / visa, it is most likely a scam!