Missing Data and incorrect format

HI, hope you are doing well, i am currently learning POWER BI DAX Course, in which i am facing difficulties, the Data resource which is provided in the course with the name Data excel worksheet, there are some coulmns, missing from the actual data for eg Sales amount ENR, Sales order line number from the FACTINTERNETSALES table, and also the columns named Currency code and other values after the Total product cost from FACTINTERNETSALES are all NULL values with no column names, i dont understand how to coop up with this, please assist. all issues can be found when you load data in excel