what is it about roaming that you are trying to sort out?
If you are going abroad, log into your account . Click on the "Plan and device" tab (near the top of the page).
Go to "Manage my services" set "Roaming" to ON & "International call barring" to OFF
If you want to say thanks > click 'Kudos'.Answered your question? > click 'Mark as Helpful Answer' also.
once you've logged into your account (the account in question if you've more than one number in your account "Hub").
There are a row of "Tabs" (selectable options) near the top of the page. Click on the "Plan and device" one.
(I'm using a PC to look at my account as i write this so it may be slightly different if you're looking on your phone or tablet)