This image was rejected due to quality issues, any feedback and tips for editing in lightroom would be greatly appreciated.
Black and white conversions are not accepted.
Black and white pictures are rarely accepted. In addition, the focussing is limit and the picture exposes some noise.
Even at 200% this should show more detail and sharpness:
For submitting to stock, don't convert to greyscale, buyers can do this themselves.
As for tips in Lightroom, there are a lot of Adobe tutorials. Be aware though there are two versions of Lightroom. Lightroom Classic which is the original Lightroom, and Lightroom, which is cloud based, and often used with mobile devices.
Quality issues are varied and can refer to exposure, focus, composition, etc.
The other bird should probably also be in focus. Because the other bird is out of focus, I think it makes the composition a bit unbalanced.
Your depth of field was just too shallow here, resulting in very little being in focus.