you

The word "you" doesn't always mean the person who you're directly speaking with. Sometimes it means "people in general" or "anyone".

Here are some examples of "you" used in a general way:

You need a solid foundation in basic math and science.

You can't beat face-to-face communication, you know?

In very formal English, you can use "one" instead of "you":

One is able to convey subtle nuances through face-to-face communication that are not possible to convey through other means.

fill out (a form)

A "form" is a document with blank lines or boxes that you write information into. Forms were originally printed on paper, but now forms are common on the Internet. You can see them whenever you sign up for a new website and have to enter your name, email address, and other information.

To "fill out" a form means to write answers into the blank lines or boxes.

Here are some words that you can use after "fill out":

fill out an application

fill out paperwork

fill out a registration form

fill out a survey

a bunch of (something)

"A bunch" means "a lot" or "many":

We have a bunch of leftovers. Why don't you take some home?

I lost a bunch of money on the stock market.

It's a casual expression and can sound kind of childlike.

paperwork

"Paperwork" describes forms, applications, records, contracts, and other documents which a person has to deal with.

We often use the word like this:

You wouldn't believe how much paperwork I had to fill out in order to get them shipped here.

I thought about doing it myself, but then I realized that there was way too much paperwork involved and so I got an accountant.

In other words, "paperwork" is something that people often complain about.