To send a text message from a Yahoo email account to a cell phone, you can follow these steps:
1. Open your Yahoo email account and click on "Compose" to create a new email message.
2. In the "To" field, enter the recipient's 10-digit phone number, followed by the appropriate SMS gateway address for their mobile carrier.
3. You can find a list of SMS gateway addresses for major carriers here: https://www.notepage.net/smtp.htm
In the subject line, enter the message you want to send.
4. Type your message in the body of the email.
Click "Send."
The recipient will receive your message as a text message on their cell phone.