Making Gantt Charts is an extensive topic. But here I will focus on Gantt charts for research purposes.
Definition: A Gantt chart, or harmonogram, is a type of bar chart that illustrates a project schedule. This chart lists the tasks to be performed on the vertical axis, and time intervals on the horizontal axis. The width of the horizontal bars in the graph shows the duration of each activity. Gantt charts illustrate the start and finish dates of the terminal elements and summary elements of a project. [efn_note]Taken from Wikipedia (https://en.wikipedia.org/wiki/Gantt_chart) on 24th Nov. 2020.[/efn_note]
Following material will help you in marking simple Gantt Charts.