Hi Jennifer,
Thanks for reaching out with your question about BoldGrid Post and Page Builder for WordPress!
In order to add a new text box to a block you simply need to click inside the block and start typing. You may need to adjust the padding, margin, or vertical/horizontal alignment of the block in order to position the text exactly the way you want.
If you hover over the newly added text you should see the orange “content” options toggle which will allow you to set the controls for your text block.
I hope this helps. Please reach back out if you have any other questions for us