It design for you to build credit you pay the £8 per mouth they then report that the the credit ref and then after say 12 mouths or how long you keep it up it show as a good line of credit it’s a but like cash plus credit builder they lead you money that you can not use you then pay that’s off over 12 mouth and when you finish they report.
It’s meant to show you can get some credit on you score it might help to improve it I don’t totally sure it’s nit a credit card really you cannot use it.
They is credit building cards out the also might help as long as you use them in the right away.