Open your Google Slides presentation
Select the text box or highlight the text you want to turn into bullets
Click the Bulleted list icon in the toolbar
If needed, click the small arrow next to the Bulleted list icon to choose a bullet style
To add a bullet point on a new line, press Enter
To create a sub-bullet, press Tab
To move a sub-bullet back to the main level, press Shift + Tab
To remove bullets, select the bulleted text and click the Bulleted list icon again