There are various alternatives:

You can create a Spanish company. Once the company is registered for social security, you can set up the payroll for the employees. Within this option we must distinguish:

• Register your foreign business (If you have a well-established business outside Spain, but you don't plan on having a physical office in Spain, we can offer you this possibility but it should only be used for those who wish to get to know the country before establishing)
• To set up a Sucursal
• To set up a new Ltd company
• To buy an already made Ltd company