Build a Geographical Information System within my website

Within my website I want to give a GIS service. I want clients to be able to generate maps. What I envision is that the client uploads a kmz file of an area and the system compares it with a data base that I will provide, after this, the system should generate a pdf file with the map resembling the attached document. I will provide all data bases but the user has to be able to upload the kmz with the area that is going to be analyzed, after this, the system will be able to generate a 5 kms buffer and include in the map and in the table of contents, the information taken from the databases that will be provided.