when you made plans about future you can say ''i am (verb)ing ....'' (it means it is probably going to happen, i made a plan) although the grammer looks like present the sentence still indicates future. (you better use time adverbs in these kind of sentences)

Which city of India is called pink city? (I think the answer is Jaipur)

quadruple

It means they gave him nothing, they didn't give him food and clothes. This is 'neither .. nor ..' form and has negative meaning. They didn't give him either food or clothes. (this sentence has exactly same meaning with your sentence)

are

grass

"I made a cake yesterday" is correct, your verb have to be past form because you did it yesterday

both are completely correct, you can use each one

What is calcium deficiency? Calcium deficiency means there is less calcium than necessary.

gonna means going to, wanna means want to.