what does the below rebus means?

If we tell you that there is a relation between the numbers and letters in the given figure, can you analyze it and find the missing letter in the last box?

There's a day, that comes around once a year.
To celebrate the man, you hold dear.
He gave you life, love and will pick you up if you fall.
When it comes to guys like him, He's the best of all.
Who is he?

An ape is trying to climb on a pole that is 60 feet high. Due to the slippery surface, the ape climbs 3 feet in a minute only to slip back 2 feet.

How much time do you think the monkey will take to reach the top of the pole?

A man is looking at a photograph of someone. His friend asks who it is. The man replies, “Brothers and sisters, I have none. But that man’s father is my father’s son.” Who was in the photograph?

The day after tomorrow will be three days before Tuesday. Can you find out what is today?

How many words can a quill made with the feather of a pigeon write with a 100ml bottle of black ink?

Solve the counting riddle by identifying the number of triangles in the given picture.

Buy me, smell me or deliver me, I do not change.

Who am I?

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?