Hi Ali,
in excel file you should have coordinates (LONGITUDE and LATITUDE) in decimal format. Open MapInfo, open excel file, on “Excel Information” dialog box check “Use row above……for Column Titles”,on “Set field properties” click OK (unless you like to change field type for each field) and a table appears. That’s a TAB file. If you like to show in the map, click Table-Create Points, select the table, Get X Coordinate from Column (that is column with longitude) Get Y Coordinate from Column (that is column from latitude), click “Projection …”, Category=Longitude/Latitude, Category Members=Longitude/Latitude (WGS 84), OK, OK and that’s it. Hope it helps.