This is a classic problem that reveals a deeper truth about how most people still use spreadsheets. You have two sheets, a master file and a diagram, and you want typing a store number in one cell to pull the correct address from another. The solution is a simple `VLOOKUP` or `XLOOKUP` formula, and the community will give you that answer quickly. But what this request really shows is that you are already thinking like someone who expects software to do the heavy lifting. The fact that you asked the question at all means you are ready to move beyond manual lookups and into a more automated workflow.
In practical terms, what you need is a formula in the address column of your Master File that says, in plain English, "Look at this store number, find its match in the Diagram sheet, and return the address next to it." In Excel 365, `XLOOKUP` is the cleanest option. If your store number is in cell A2 of the Master File, and the Diagram sheet has store numbers in G:G and addresses in H:H, the formula would be `=XLOOKUP(A2, Diagram!G:G, Diagram!H:H)`. That is it. Once that formula is in cell F2, you can drag it down the column. Every time you enter a store number in column A, the address appears automatically. No copying, no searching, no double-checking.
What this means for your daily work is that you stop being a data entry clerk and start being a data manager. The master file becomes a living document instead of a static record. You can add new store numbers as they come in, and the addresses populate without extra effort. This is the difference between maintaining a list and building a system. The spreadsheet is no longer a container for information you type; it becomes a tool that connects information for you. That is a small shift in technique but a large shift in mindset.
The real point here is not about which function to use. It is about recognizing that the spreadsheet itself can be the automation layer. You do not need a separate database or a custom application to solve this. You need one formula applied once. That is the power of modern spreadsheets when you let them work the way they were designed. So go ahead and write that formula. Then, the next time you find yourself repeating a manual step, ask yourself if a formula can do it instead. The answer will almost always be yes.