What should be considered when e-mailing a beginner?

Question

Mail server

There is a large database of email addresses of about 100 thousand, most of them are foreigners.
1. What software to use to make a newsletter
2. What you should pay attention to.
3. What not to do (are there any limits per day, how not to get into spam filters)
4. Can your own VPS server help in this endeavor.
I would be very grateful for the answers.

Answer 1

You should consider some kind of Unisender or Mailchimp