First of all, in ANY country and especially Latin American countries, there is ALWAYS bureaucracy involved and it is generally difficult to聽 deal with them, as well as being costly and time-consuming for foreigners.
I would suggest you do an internet search for
paraguay trabajar como extranjero
...and read the links that come up, for instance:
The last link above is a page of La Direcci贸n Nacional de Migraci贸n, who make the determinations of eligibility and control changes of visa.聽 It does appear that as a tourist you can petition them for a change of visa category without leaving the country - normally in any country, you are NOT allowed to work while on a tourist visa.
I encourage you to get in touch with La Direcci贸n Nacional de Migraci贸n to get the correct and up-to-date information.聽 Here is their main web page:
But I caution you - without being able to fluently read, write and speak Spanish or Guaran铆 (the two national languages of Paraguay) you will find it difficult to impossible to do what you plan.
