Color Photo to B&W with One Object Colored

This can be done in Lightroom if the shirt is the almost the only thing in the image that has that approximate color hue. In that case, you can go to the HSL color panel (it's hidden normally but can be disclosed by clicking the little colored circle icon (see here for screenshot: Lightroom CC: Where are the HSL adjustments? | Photoshop Family Customer Community))​ Then dial the saturation of all the colors except the colored shirt. This should turn almost everything black and white except the shirt. Then if there are areas left over that are still colored but you want them black and white. Just brush them away with a brush set to -100 saturation.

It's much easier to do in Photoshop but it does work.

You would need to reply in a web browser and add the color photo so we can see what you need.

It is normally done in Photoshop using layers.