Email List Collection -- Google or MailerLite

I'm trying to figure out email marketing and list collection. I have a free mailerlite account, but I also pay for my own website email through Google Workspace. Of course, I have no idea which is better, and so I thought I would ask people here.

I want to make it so that when people go to my website (xandland.com) and sign up for the Xandlist, they'll receive in their email a link to where they can download a free file for signing up. I have no idea how to do that.

I've tried connecting my mailerlite account to my squarespace/website account, but so far haven't been able to figure it out. Mailerlite wants me to create a CNAME and a TXT record, and I have no idea what I'm doing.

But, if I have the Google Workspace email, do I even need Mailerlite? Can I create campaign and automate sending links for free files with just Google? Can I create unique landing pages, etc.?