Any software to automate email REPLIES in real time?

Hey,
So I'm sending out tons of emails and I'm getting back replies to my inbox. I used to copy-paste replies but I want to scale it up and send back 100+ emails daily so I was wondering if

there is any solution for automated replies based on keywords used in email?

For example, I want ro run a sequence of emails. If the first reply has "yes send it" in it, it would automatically send back already prepared email (and even better if with the use of Spintax) etc. etc.

I just want to automate the whole process and have the system checking for the specific keywords in received mail, then automatically reply.

I use gmail.

Do you guys know of any software that does this?

Thank you!

Microsoft Outlook email processing rules can do that?

I think you can do it with Outlook mail. Kindly go to account settings in the mail and check out whether it is conceivable.
Hope you can send automated replies by saving them as a draft. If you're interested just have a try.

Most of email marketing tools have build in autoresponder feature as Interspire and Mailwhizz.

If you don't necessarily need spintax, with Gmail you don't need a third party tool for this. It can be achieved within Gmail by enabling and creating a template for automated replies, then setting up an automatic reply filter using the desired keyword(s) in the email body.

Here's the step by step for the process: https://www.lifewire.com/how-to-send-canned-replies-automatically-in-gmail-1172080
You can follow it from word to word. When you're at the stage to create the filter, you need to add your keywords to the "Has the words" field. It will be clear, when you're there.

It's often overlooked, but a lot can be achieved, when Gmail filters are used right.

You should check out Mailshake
It's super easy to set up

Mailchimp - can send an automated email when someone subscribes to your audience or purchases a certain product. Mailchimp offers a wide selection of preset automation types with built-in triggers, ranging from abandoned cart emails to a simple welcome message.
Omnisend - Best email autoresponder for ecommerce.
GetResponse - Most flexible email autoresponder.