First you have to convert .SIE file into excel as mentioned in this article - SIE to EXCEL. Then to load an Excel file into MATLAB, you can use the xlsread function. Here is an example code that demonstrates how to use xlsread:
filename = 'your_file.xlsx';
[data, headers] = xlsread(filename);
disp(data)
disp(headers)
In this example, you should replace "your_file.xlsx" with the actual name of your Excel file. The xlsread function reads the numeric data from the Excel file and returns it as a matrix. The second output argument headers returns the cell array of strings containing the column headers from the Excel file.
Note that xlsread can only read data from the first worksheet in an Excel file. If your data is in a different worksheet, you will need to specify the worksheet name or index as an additional input argument to xlsread. You can find more information on the syntax and usage of xlsread in this MATLAB documentation.