Without data, there is not much Excel can do. Formulas will have no data to work on. Charts will not show anything. Data is very important to Excel. There are things you can do without it, like draw shapes, but Excel is designed to do things with data, so you need to have some.
Excel files will have data in them, so in that way they are storing data. Excel is not a disk or USB key or other such data storage devices. It is software, not hardware.
Use the delete key.
In Excel, you cannot use the Escape (Esc) key to enter data in a cell.
Ctrl - End.
It would use the data in the column as the basis for the sorting and sort the rest of the data.
You can copy data from Access and paste it directly into Excel. From a table or query, data can be selected and then copied and pasted into Excel. In that case, data changing in the original Access file will not change data in the Excel file. To do that there must be a link between the data. You can also import data from Access into Excel and from Excel into Access, again maintaining a link to the source if you want.
There are hundreds of reasons. You press the Enter key when you want to execute whatever command is appropriate at the time. If you are entering data in an Excel worksheet cell, you can press the enter key when you are done entering the data.
The only thing that happens is that only the data which meets the terms of all the filters is displayed.
It is data coming from another source, such as a database. It is external to Excel, but being used by Excel.
Excel is primarily a spreadsheet, not a database, so you do not set primary keys in it. That would be something you would do in a program like Access. Setting a primary key ensures that there is a unique value in each record, meaning that record can always be uniquely identified. Without a primary key set, it is possible to end up with duplicated data and it can be harder to find data. Primary keys are also used in creating relationships, so that is more difficult to do without one.
Press the Enter key. Click on the tick beside the formula bar when you are typing it in.
A chart is a visual representation of data in Excel.