Good morning. 

I like this plant and bought it a few years ago. Now it has grown taller it looks tired. It is in a 15 inch pot in an area that gets the afternoon sun. I have given it some 20-20-20 fertilizer pellets. But it remains the same. I wonder if I should cut it back but I don't want to kill it. Any help would be appreciated. 

Thank you. 

https://www.picturethisai.com/app?gclid=EAIaIQobChMImambie779gIVh7jICh3i7Q8yEAAYASAAEgJZSfD_BwE

 

The above link will assist using your smart device 

I think it some sort of succulent, and looks pretty health flower, probably not needing much water, however just guessing

Take a picture with your regular camera, then open up that picture in the Google Photos app. Next, tap on the Google Lens button at the bottom of the screen. It will tell you what kind of flower this is within seconds.25 Mar 2022

 

 

Maybe the plant is root bound.  

Possibly a Euphorbia tithymaloides? -White sap?

Put it in a bigger pot whatever it is!

It looks like a Euphorbia bracteata, commonly called a Tall slipper plant.