How Do I Activate Intersect On My Coreldraw?

Hello,

I am new here, and I am also a beginner (so to speak) when it comes to corel draw.

I encountered a problem while using my coreldraw 12. I suddenly discovered that when I try to intersect a bitmap into an irregular shape like I used to, intersect, weld and others in that category no longer highlight for me to select.

Please who can help me out? I need to complete a design urgently.

Thanks in advance.