is there any way to change the dropdown to serach? link to Power Query

bbsin 

So long as you type a name correctly (or at least reflect accurately the same way it's listed in the table of table assignments), the FILTER function would work. Set the last name as the primary criterion, have the person doing the searching type in that last name and Excel will list each person with that last name and their table assignments (and whatever else is in your full database that you wish).

The formula would read something like this

=FILTER(GuestList,(GuestList[LastName]>'Search Sheet'!B1),"Not found")

where "GuestList" is the name assigned to the guest list database,

"LastName" is the column heading for last names

and 'Search Sheet'!B1 refers to the cell in which you type the last name to be found

That would return from your GuestList database the full row of anybody whose last name matches the typed entry.