When viewing Paramount + I cannot shut off voice over programming which appears to be for sight impaired people.
If what you are hearing sounds like an audio description of a scene (ie. Jack is walking up the stairs), then try selecting another audio track. Often these accessibility features will be termed a "descriptive track", but not always.
If this is the case, try pressing the *button on the Roku remote, look under Accessibility and Captions, then select a different Audio track if available.
From Paramount+ help pages, https://help.paramountplus.com/s/article/PD-How-do-I-turn-on-accessibility-features-like-closed-capt..., it makes no mention of alternate audio tracks, but mentions steps of disabling the Screen Reader. The Screen Reader for Roku basically describes audible actions performed on the device and not scene description. You can disable screen reader from the same menu mentioned above, or from within Roku Settings. (Settings/Accessibility/Screen Reader).