You can't. The standard line chart object in Qlik Sense supports only one dimension for the x-axis. But if you have a datetime (aka timestamp) dimension you can use that and Qlik Sense will automatically show the appropriate unit when you zoom in.
For our case, for each date we having 48 periods. Thus would like to check if it is possible to display the period above the date on the X axis? Or is there any extension tools which can help me to achieve this?