While importing data into PowerBI we can choose the tables we want to load in the data model but we cant choose specific columns, although columns can be removed through advanced editor or by manually deleting them one by one this can also be done without using advance editor and multiple columns or tables can be deleted at once. To do this go into the data model section of your PowerBI report.
Now expand the desired table and the press ctrl key on your keyboard and select the columns you want to delete. You can also select multiple tables using the same instruction.
After selecting multiples columns or tables right click and select “Delete from the model” option.
In the dialogue box that appears click on the “Delete” button.
Then click on “Apply Changes” option which will appear in the window and you can see all those columns are now deleted
Hope this helps!