Can you check this paragraph for me, please?

1) A few weeks ago my cousins had an incredible sequence of accidents; he wanted to make a coke for his mother but he couldn't reach the eggs and the flour that were in a very high part of his kitchen's furniture.
2) So he went on a chair but he suddenly fell off the chair and knocked over the eggs that broke on his head.
3) A bottle of oil that was near the eggs and was made of glass fell down too and knocked over his mobile phone that completely smashed with the bottle, whose oil fell onto the floor.
4) He only wanted to make a cake!

Thank you.

1) The word "cousins" should either be singular or you should say "one of my cousins".

2) Did all of the eggs break on his head? Or did some break on the floor. I would recommend
" and knocked over the eggs, (some of) which broke on his head.

I would prefer shorter sentences with not so many conjunctions and clauses not separated by commas. That is a matter of style.

3) Same comment about sentence length. It is better to end with "the bottle, which broke and spread (or spilled) oil all over the floor." One would expect the oil to fall with bottle.

4) Nice ending!