Here are some ways to send text messages from your computer:

1. **Using Cortana**:
- Go into Settings and toggle on Send notifications between devices.
- Optionally, you can also enable Use Cortana Even When My Device is Locked.
- Enable Cortana by selecting inside the search box in the Taskbar, then select the Notebook icon. You're now in Cortana's settings.
- Next, select the Settings icon and toggle on Hey Cortana. Now you're ready to text from your computer.

2. **Using Google Voice**:
- Go to voice.google.com on your computer.
- Open the tab for Messages.
- Click the text message you want to reply to.
- At the bottom, enter your message, and click Send.

3. **Using Microsoft's Phone Link App**:
- If you haven't already set up messages, do the following:
- On your PC, in the Phone Link app, select Messages.
- To start a new conversation, select New message.
- Enter the name or phone number of a contact.
- Select the person you want to send a message to. A new message thread opens for you to begin.

4. **Using Email**:
- Open your web browser and sign in to your email account.
- Compose a new email and type your recipient’s phone number in the “to” box. Then append their phone number with the SMS gateway. For example, if their phone number is 123-456-7890 and they use AT&T as their carrier, you would type 1234567890@txt.att.net.