I´m planning to be a pilot, i just want to know if you can work only with the private licence and where.
You cannot do so. A private pilot’s license - at least in the US - prohibits you from offering airman services for compensation or hire.
If you intend to fly professionally, you will need at least a commercial pilot’s certificate. An instrument rating is also highly recommended as is multi engine class ratings for the greatest chances of employment. Air carrier operation will require you to hold an airline transport pilot’s license for part 121 operations.
The opportunities are limited, as the FAA pretty loosely construes compensation. For example, you cannot fly to take photographs, which you sell.
You can conduct operations which are incidental to your work. For example, if your business required you to be in different locations, you may be able to fly to those locations, similarly to driving there. I do not believe that you could haul product or customers. If you are considering this type of work you should consult an aviation attorney. I would search the FAA Letters of Interpretation (LOI) first before spending money on an attorney.
There are some other things you can do, as a private pilot. For example, I have an uncle who is a farmer, and conducts Part 137 ag operations on his farm. Sometimes he hires other pilots, and they need commercial licenses. However, he can apply chemicals to HIS farm land without a commercial.
In general, having a private pilot license may help show a level of experience which may help you acquire non-flying jobs, but I suspect you are not interested in that.
The entry point for most pilots is commercial/instrument/cfi, however I have known a few pilots who had just commercial/instrument, who built hours towing banners, towing gliders, flying jumpers and as SIC for 135 operations. Some, who are good at networking, may get jobs flying for Part 91 corporate ops, but with low hours, the insurance requirements are steep. Building hours is the primary reason why many pilots get an instructor rating. That motivation may not assure the best instructors, but that is how the industry is currently structured.