Ask HN: What's the best way to manager email campaigns

I am totally new to email marketing. And I wish I can get some experienced marketers to explain me about how to manage the email marketing campaigns.

Currently, I collected average 10 contacts (email, first/last names) from 30+ brands, and put them in Google spreadsheet. I am planning to use MailChimp. Before I jump on it, I have two questions.

Q1: I want to know which one is good idea (practice) to manage these contacts

1) keep these contacts in google spreadsheet and update/organize them according to campaigns status (open, bounce, click etc)

2) totally rely on MailChimp to manage the contacts.

Q2: I am a little worry if there is one day I need to migrate these contacts to another email marketing tool or sales tool, or it's quite normal that people manage contacts, campaigns across different tools at the same time?

Thanks in advanced.

Try not be discovered by my boss, I registered this new account to ask. Sorry about this.