In this study, we have first introduced a generalized concept of soft S-metric space based on soft points of soft sets and renamed it "Soft $S_b$-Metric Space". We have also discussed the relation between soft S-metric spaces and soft $S_b$-metric spaces with an example. After that, we gave some definitions with examples (such as symmetric soft $S_b$-metric spaces, convergent of a sequence of soft points, Cauchy sequence, completeness etc.). Next, we have proved some properties regarding soft $S_b$-metric spaces with example. Then, we have proved some important results on soft $S_b$-metric spaces. Finally, we have proved a unique common fixed point theorem of two soft mappings satisfying a few conditions and with the help of this result we have proved a corollary that if these two soft mappings are the same then we can get a unique fixed soft point. We have also discussed this corollary in details with a suitable example as its application.