Wordplay question, Please help. I am English learner, for the following two questions, I have difficulty to make a choice.?

1.You will need to apply online. To do ___ , please click on the following link.
it
one
this
such
2. ___ director of Customer Services, I would like to thank you for your recent
email.
How
Like
As
Being
In question 1, I’m struggling to make a choice between “it” and “this”. In question 2, I am struggling to make a choice between “As”
And “Being”. For my limited English knowledge, it’s hard to know the nuance between them. I even think the both are the same! I really don’t get it, any explanation will be a gift to me, thanks, very much.