This paper explores stock exchanges as central venues for trading securities, tracing their historical development and significance, and examining their contemporary divisions. It also provides insights into the world's most significant stock exchanges: the New York Stock Exchange, Tokyo Stock Exchange, London Stock Exchange, and the local Zagreb Stock Exchange. The paper delves into the procedures of trading and buying stocks, as well as securities market analysis. By conducting fundamental and technical analyses of two related companies, Maistra d.d. and Adris Grupa d.d., the paper illustrates the process that investors undergo to gather information about a company's performance. The paper demonstrates how various capital markets function when faced with unpredictable challenges, such as the COVID-19 pandemic. To achieve this, stock market indices are used to monitor and measure the success of both the capital market and the entire country. Analyzing the movement of indices from the mentioned stock exchanges, the results indicate that all observed capital markets were in development before the onset of the pandemic. With the introduction of strict restrictive measures, there was a sudden decline in trading volumes on the stock exchanges and their indices. Although the initial drop was significant and unexpected, the observed stock markets recovered from the initial shock within a few months and resumed daily growth.