Hello Jone,
Hope you're doing well.
As far as I understood, you want to change the value for Nuber column in your entity for those specific records.
It seems that your entity has a composite key (Rel + Cliente attributes), so you need to filter by those 2 fields.
So you can use an SQL tool for that:

Something like this should do the trick:
UPDATE your_entity
SET nuber = 1
WHERE rel = 2 and Client = 'B'
Kind regards,
Rui Barradas