There are two main ideas of this Master thesis. The first idea of the thesis is that the paper systematically looks like a main design. Therefore, the paper is divided into five basic units. In the first part Introduction the reader is descriptively introduced into the meaning and goal of the paper. Second part The general part lists the introductory content that each major project must have. Then, in the third part, Quality Control and Assurance Program, guidelines and conditions that must be met by construction works, installation elements and materials in order to achieve and maintain satisfactory quality and durability of the building are given. In the fourth part, the Calculation of Mechanical Resistance and Stability, there is a complete calculation of effects on the structure, dimensioning of elements and calculation of connections. Fifth unit Conclusion synthesizes the results of the work. The other idea of the paper is to get an insight into how the structure behaves in the case when the dominant effect is no longer an earthquake but a wind. More precisely, according to the existing project, the structure is on the ground of high seismicity and according to this paper, the structure is located at a location where the wind load is taken as dominant. Sizing of the steel structure of the center for social and functional purposes was carried out using the software package Autodesk Robot Structural Analysis Professional. The resistance of structural elements for the ultimate load capacity and serviceability limit according to European Standards for steel structures and the National Annex for use in the Republic of Croatia (HRN EN 1991, HRN EN 1993) was tested. The calculation of characteristic connections was performed using the IDEA StatiCa software package.