What does this below rebus puzzle mean?

Keyboard words are not in alphabetical order, Why?

I come in different shapes and sizes.
Parts of me are curved, other parts are straight.
You can put me anywhere you like,
but there is only one right place for me.
What am I?

There are nine letters in the below-given diagram. You have to form a nine-letter word using these letters.

A boy and his father are caught in a traffic accident, and the father dies. Immediately the boy is rushed to a hospital, suffering from injuries. But the attending surgeon at the hospital, upon seeing the boy, says 'I cannot operate. This boy is my son.' How is this situation explained?

I am a mother. However, I never give birth.

I am a father. However, I never nurse my children.

Wandering is not possible for me, but standing still happens occurs rarely.

Who am I?

Find the next number in the sequence

5 12 24 36 ?

You board a train. The train will have to enter a tunnel soon. You are claustrophobic. Which place is the best for you to sit?

Decode below three cipher riddles:

26 L of the A
7 D of the W
1000 Y in a M

How high do you have to count before you use the letter “a” in the English spelling of the whole number?