If you have an existing line you'll need to set up your eSIM as above. Once the set up is complete you'll see that you have a second line but no phone number is present. You simply need to go to www.ee.co.uk/simswapand follow the instructions.
You’ll need the SIM serial number from your eSIM card pack and be able to receive a pin verification to your old SIM. If you aren’t able to use your old SIM you’ll need to call us on 150 from your EE phone so we can swap the number over for you.