It is not very clear as to what you want from the explanation in the worksheet but one thing you are doing is using merged cells.
Originally I need let this cell read from Reqs for offer Sheet and if there is change I want select from the Drop-down list or I can edit by writing the new position and next offer I want comeback to the original witch read from Reqs for Offer.
If you want your drop-down list to expand to take new entry's in the Data sheet turn it into a table
Avoid merging cells
Merged cells can help you arrange values in a meaningful way, but they come with problems -- numerous problems, big problems.
For instance, Excel won't apply column formats to a merged cell unless you select all the columns that comprise the merge.
In addition, not all cell formats stick once you unmerge a cell.
You can't sort a column with merged cells.
You can't even select a single-column range if there's a merged cell in it -- go ahead, try!, the whole column will become merged, not good.
You cannot put a filter on it. The problem is the filter is completely useless because the filter will groan with the "merged cells need to be identically sized." Warning, which in English means you have to make each group of merged cells the same size as the largest group. And you have to find them all!
Merging cells in columns and rows could lead to data lose, bad thing.
Formulas and Functions that refer to merged cells will not work, bad thing.
Don't hesitate to use merged cells if you really need them (you don’t), but they
will limit what you can do to the cells and even the columns involved.
Center Across Selection is a far better alternative to merging.
To apply this format, select the cells you want to appear merged and then launch the Alignment group dialog, Ctrl + 1, and click the Alignment tab. Center Across Selection is in the Horizontal drop-down.
You will get the desired look you want but without the merged cells problems.
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