It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

What is the word or phrase?

I am something people love or hate. I change peoples appearances and thoughts. If a person takes care of them self I will go up even higher. To some people I will fool them. To others I am a mystery. Some people might want to try and hide me but I will show. No matter how hard people try I will Never go down. What am I?

Can you fill the blank with the correct number?

6 30 870 756030 _____

You bought me for dinner but never eat me. What am I?

A kind heart person buy packed food at 3$/packet from United states and sells them at 1$/packet at Africa. After some time he becomes a millionaire.

How come the guy become millionaire ?

What can run but never walk, have a mouth that never speaks, have a head that never weeps, and have a bed but never sleeps?

Can you count the number of squares in the figure below?

As a whole I am both
safe and secure.

Behead me and I become
a place of meeting.

Behead me again and I am
the partner of ready.

Restore me, and I become
the domain of beasts.

What am I?

Decode the movie name from the below picture?