To bring up the Properties palette, right-click on the text you want to edit and choose Properties. Make any necessary changes to the properties, such as the Font or the Obliquing angle. Double-click the text to open it in the text editor and make changes to particular parts of it.
The TXT2MTXT command, which is accessible in all versions of AutoCAD* that have the Express Tools loaded, provides the solution. The command is also available in the Ribbon Insert tab Import panel for AutoCAD and AutoCAD LT 2017.1. 2.
Single-line text is formatted in the same way as multiline text is formatted. You attach an existing style to text by typing its name in the Style window when creating new text. Use multiline text instead of single-line text if you need to apply styling to individual words and characters.
Multiline Text Editing:
Select a multiline text object by double-clicking it. Enter the new text in the In-Place Text Editor. Use one of the following techniques to save your changes and quit the editor: On the Close panel of the Text Editor ribbon contextual tab, click Close Text Editor.
MTEXT (Command) Commands is for Creating Notes and Labels Text