1. Draw a circle.
2. Select your text
3. shift click your circle
4. go text/fit text to path
p.s. can't do it if the text is converted to curves. you have to fit to circle first then add your effects
According with the image, it seems that the text has a Contour ffect applied. If you select both text with contour, the option for "fit text to path" was disabled, but if you select only the text (using the tab key or selecting the text on the Object Manager), you can go to text/fit text to path and choose the circle as path