To create a Yahoo mail account on your iPhone, you have to follow all the below-given steps:
Firstly, navigate yourself to the settings.
Make your way to the mail and then to the accounts.
Go with the option of Add account and then pick one.
Fill in your Yahoo email address, and click on Next.
Then type the password you want to make for your account and instantly click on the sign-in tab.
After all of this, you need to mail the toggle switch.
Finally, click on Save.