I want to know:
1) While doing ghusl, is it compulsory to remove the pores that's on my face which would come out if used face scrub or done anything such to remove it?

2) When blood comes from skin it sometimes becomes dry in the spot and it remains stuck to the skin so its healed. So do I need to compulsorily try to remove such spots of blood and see if it comes out or not by scratching by finger?

3) If there is skin thats little hanging and can be removed by cutting it by using nail cutter then its compulsory to cut it before ghusl?

You should not do anything of what you have mentioned in your question before doing Ghusl. The only thing you should do not to leave anything which is barrier for reaching water to your skin and that is not amongst your body parts.