models
Modeling and talent agencies are required to have licenses in order to operate their businesses but are not required to provide any kind of care to their models/actors, since those individuals are independent contractors and not employees of the agency.
You do not need to go to school for modeling or take any kind of classes. When you sign with a modeling agency they will train you for free and begin getting you work.
When you sign with a modeling agency, they will be responsible for training you at no cost. They will teach you the proper posture, how to walk and how to carry yourself on a catwalk.
If I understand your question correctly, you are asking about where modeling agencies do business? If so, modeling agencies are held in office buildings (usually a suite) with multiple rooms, one for the bookers, a lobby/waiting room, and a few rooms for picture taking and interviews. Some modeling agencies are solely online and do not have an actual location for models to go to but it is usually better to work with a traditional modeling agency with a physical location you can go to.
Unfortunately, there is no market demand for male models under 5'10". There is no petite modeling for men, either. The only way to do any type of modeling is through freelance, which means that you work as a model without an agency and act as your own booking agent. There are hardly any modeling agencies that will sign on a 5'7" male, unless you are a teen.
There is no uniform for modeling. You wear what you are told.
Kind of Employees Supervised by You
a fashion model must work with the agents and bookers at their modeling agency as well as with designers, photographers, hair and make-up artists and other models
It would be useful if you were to say what kind(s) of writing you have in mind. Creative writers are nearly always freelance (self-employed), for example. If you want to be employed as a writer, your best bet might be working for an advertising agency or newpaper.
While such laws vary from country to country, more than likely you will have to have a business license of some kind in order to legally operate a modeling agency. It is best to check with the government website of Paris to get more detailed information.
You'll have to send your headshot and photos to modeling agencies that represent the type of modeling you meet the requirements for. It is best to look into agencies that are within a 2 hour's drive of where you live. Check out the agency websites, which will give you information about what kind of photos to send, if they hold open casting calls, and how to send them (snail mail, email, etc).
People who are self-employed have to pay taxes on their income just like people who are employed by a company. They also have to pay a "self-employment tax" that basically makes up for the fact that they haven't been paying FICA taxes.