The easiest way to select the record with the maximum value (instead of just finding the maximum value) is to sort the records in descending order on that field. You can either sort the records in a found set or in a portal of sorted records.
Either way, the first record will then hold the maximum value and you can use Go to Record [first] (sorted found set) or Go to Portal Row [First] (Sorted portal) to find the record with the maximum value.
To move values to records in other tables, one generally uses either Set Variable and/or Set Field to move the data.
It might look like this:
Go To Layout ["YourLayout" (YourTable)]
Show All Records
Sort Records [No dialog, Restore] //sort in descending order so max value record is first
Go to Record [first]
Set Variable [$Name; value: YourTable::NameField]
Go To layout [Some other layout (Some other table)]
Perform Find [restore] // do something here to find the record you want to receive this data
Set Field [Yourothertable::NameField; $Name]
This is very general and there are a lot of variations possible.