During the import, as you preview the dataset to be imported, you have an option to change the number of header rows in the Your Options panel. This value is set to 1 by default and could be set to 0 in your use-case. When you set this to 0, the columns will be named column1, column2, column3, etc. You have an option to modify the column names in the Preview panel.
Here's the guide to importing datasets.