relate to (someone)

To "relate to" someone means to feel comfortable with them, and to understand each other. People usually relate to each other by sharing information about themselves.

If someone always wanted to talk about sports, but you weren't interested in sports, you might have trouble relating to them. Here's another example:

I was glad to finally meet someone who I could relate to.

You have to (do something)

Use "you have to ___" when you're giving someone advice, especially when you're an expert or know more than the other person. For example:

The bottom line is that you have to reduce your calorie intake to lose weight.

As (something), (sentence)

This expression is useful for describing who a sentence is about. It's easiest to understand it with a few examples:

As a parent, I have to think about what's best for my kids, not just myself.

As the oldest member of the team, I feel like I'm held to a really high standard of performance.

As my friend, tell me the truth: do you think I'm making a huge mistake? 

You can see from the examples that "As ___" works for talking about yourself or for talking about other people. 

a wide range of (people/things)

A "wide range" means a lot of things that are different from each other.

For example:

You should try to eat a wide range of fruits and vegetables.

They had a wide range of different lamps, but none of them really appealed to me.

"A wide range..." sounds rather technical or scienticfic. People use it when explaining things.