You can select the points on the plot and save it to workspace with a variable name. One of the ways to do this is to select “Data Tips” option, then select the data points to be saved. Now right click anywhere on the figure and select “Export Cursor Data to Workspace” and give a variable name.
Data Tips >> select data points >> right click >> Export Cursor Data to Workspace
To add data points to existing variable, right click and select “Create New Data Tip” then repeat above process.
Refer the figures attached for better understanding.