Mailchimp: How to auto send different lead magnets to different people based on sign-up

I run a corporate training company. I maintain a mailing list.

I want to add all webinar participants to the same mailing list, but want to
send different "lead magnet" to different webinar topic participants once they confirm their email address.

Every week, I organize different webinars and i invite public to join
e.g.
Week 1 - time management webinar, with a free time management grid worksheet sent once they sign up the webinar
Week 2 - communication webinar, with a communication style questionnaire sent once they sign up the webinar
Week 3 - project management webinar, with a Gnatt chart sent once they sign up the webinar

How can i instruct mailchimp to send time management grid worksheet to time management participants? And instruct mailchimp to send communication style questonnaires to communicate webinar participants.

Question
1)
In this case, how should I create my list?

2)
Should I create a list with different group?

3)
How can i automatically send the "lead magnet" e.g. time management grid worksheet, communication style questionnaire once they sign up?

Thank you.
dstdst123