Some English sentences to practice

I am capable trying to practice some English sentences written in different ways, such as 1º conditional, 2º conditional and 3errd conditional:

1-If I study English a lot, English I will learn it quickly.

2-If I had a ship I would/could travel by the sea. (would means you will do something, could means you can, do something).

3- If I had written a book, I would have been very famous.

For Examples of another types of sentences that I usually made mistakes with. Please, could you correct my mistakes???

He says (that or not that) the another day he was drunk.  He says that the other day he was not drunk.

I am going to talk about (that or not that) going on holidays. I am going to talk about not going on holidays.

He was writing an article called living in clouds when something happensed suddenly. (the 'was' makes this past tense)

I would like to tell you (that or not that) I am 20. I would like to tell you that I am not 20. 

When I saw you, I thought you were older than me.

Look at that! Hhave you seen that?  Look at that. Have you seen that?

Thinking of that, I need to have a solution soon. 

Please could you help me with these sentences???...sometimes I don't understand If I write properly or if I need to use more the punctuation. Correct everything, also including these explanations.

Really, thanks so much.

Well done! You seem to understand the concept of what to do. Keep working at it, you're almost there.