Clone Stamp Tool, Smart Object & Clipping Mask questions?

[imagenry_b]

I'm begginer user so I have the following enquiries: 

1- I'm unable to clone certain area using the Clone Stamp Tool nothing is happening. can you explain what's wrong in here?

Note: I attached a small video for this below.

2- Also when right clicking on the layer there are "Convert to Smart Object" & "Create Clipping Mask"

what each one is dedicated for how can I use them properly

[Ged_Traynor]

@imagenry_b check the opacity of the tool, you also need to hold the ALT key to sample from an area

https://www.photoshopessentials.com/basics/clipping-masks-essentials/

https://helpx.adobe.com/ie/photoshop/using/create-smart-objects.html

[imagenry_b]

I adjust the opacity & press alt but still no effect.

https://vimeo.com/849881935?share=copy

[Daniel R Bynum · Accepted solution]

In this particular case you had the layer mask selected on the selective color adjustment layer. You can see that because the clone stamp preview showed white, also if you look at the name of the file at the top, you'll see in perenthesis what layer you're currently on.

For your initial question, it was just the opacity was set to 1%.

[imagenry_b]

I'm waiting for an answer, please some one answer.