Work Contract on Professional Card

Dears,

I am planning to apply for a professional card in Belgium - I have all the required documents ready to be submitted. However, I was not able to get a clear answer on my question from the agency helping me with application. Hence, I am reaching out to people here.

The question(s) I have:
- Is it mandatory to have a company set up in order to have a work contract? Or
- Can the work contract be linked to my professional card?
- if it can be linked to my professional card, how will the tax/accounting be done?

If the work contract cannot be linked to my professional card, my entire investment is wasted
For the moment, I don't want to set up a company, as it is too complex (at least what I have heard).

My background: I am an Indian, working in Information Technology with  8 years experience. I will be applying for Professional Card in the same area of work.

Reason for Professional Card: Currently working as an employee of a small company (2 people company) registered in Belgium. I am a freelancer for my client but an employee for this small company. The work contract is linked between my client and the company I work for. However, this company had no involvement in getting me the job. It was on my own effort I found the job, and then I approached this company to help me with my work permit. I have been with this company for almost 8 months now, and I don't even get 25% of my actual billing. I am being ripped off by this company, hence I am planning to apply for a professional card and be on my own.

Please help!

Best Regards,
Ashok