Word Press Contact Form, MailChimp, adding Insta link

My word press website is up and running but with some errors!
1. When people complete the contact form at the bottom of each page no info is sent to my company email account, but the subscribers are showing in my Mailchimp account. I would like to receive an email so that I know there is a subscriber but couldn't see where to do this in Mailchimp (Is it possible?!)
2. When people complete the text on the contact form at the bottom of each page, their text is in black on a navy background so it's hard to read. I need the text input to be changed to white when people type in their details.
3. On the Contact Us page after filling in the form the message is "Please confirm subscription". That's fine.
4. After confirming subscription the thank you message states the company address (I don't want this showing) and 2 options; to continue to the website or manage their preferences. I want to change this message to state "Thank you for subscribing. We will be in contact with you shortly. Click here to return to the website"
5. Add Instagram link at the top of the page next to the Facebook link