Hi Solen,
If you search in google you will get much examples for your question
for sample i am giving this links
http://wiki.sdn.sap.com/wiki/display/Snippets/Creating+a+dynamic+internal+table+based+on+data
http://wiki.sdn.sap.com/wiki/display/Snippets/Example+-+create+a+dynamic+internal+table
http://wiki.sdn.sap.com/wiki/display/ABAP/Dynamic+Internal+table