Need an Formula to Lookup and get Multiple ID's as per Countries in column two

Gajapathi Muniyappa

I need to write a formula in the column ID's to bring all the ID's associated with country list like output example column (Green color in screenshot). We have multiple countries in the Country column but still it should consider the ID. Like Lookup to get multiple values as per criteria. Someone could you please help me out this.

Paul Newcome

Do you have a table built out already that has each country in its own row in one column and the associated ID in another column?