Go to visible.com. Not sure if you need to create an account first but at some point you will. Click "bring my phone" button and then you will need to see if the phone is compatible with Visible's plan. Even though he just bought it the phone might not be compatible. Just follow the steps from there. If he has an android phone it is recommended to stick with a physical SIM card as the eSIM from what I read is not working with those phone, even with an iPhone there has been some trouble.
I like the Visible for the rate and it being unlimited and I have been with Visible for 15 months, bad thing is the customer service is bad. They have no phone number to contact them so you are left with chat which has wait times of over an hour sometimes. They can be contacted via Facebook messenger which 2 weeks took 5 days for a response but yesterday I had a response within 45 minutes with subsequent replies and responses within a few minutes. There is Twitter direct message but they have ignored my last messages and going on 6 days no response. I recommend Visible but if he values customer service in a plan this might not be it.
If he decides to give Visible a try go to the savings spot forum here and find a code to save $20 on his first month. I would give you my discount code to where I also save the same but I have accrued maximum referral discounts. Whoever you chose will get $20 off also for a month.
