Step 1: Enable basic settings
First, start by enabling the basic features. This can be done by navigating to the following page in the backend:
Stores → Configuration → Cart2Quote ↓
→ License Information ↓
→ Cart2Quote License ↓
→ Activate Frontend Features: Yes.
→ Customer-Side Options (Frontend) ↓
→ Global Frontend Options ↓
→ Add Button on Category Page: Yes.
→ Dynamic add to cart/quote buttons: Yes.
→ Quotation Cart Options ↓
→ Display Mini Quote Icon: Yes.
→ Enable Mini Quote: Yes.
→ Product Page Options ↓
→ Add Button on Detail Page: Yes.
→ Advanced Options:
Step 2: Test your front-end
Start by going to one of your category pages. Because we enabled "Product Quotable by Default" & "Add Button to Category page" all your products should have an "Add to Quote" button. 
After navigating to the product page you'll see that the "Add to Quote" has also been added. This is because we also enabled the "Add Button to Product page" setting.
Now let's add the product to the quote and submit a quote request.
Step 3: test your backend
Now that you've made your first quote request let's check it out in the back-end. Start off by navigating to quotation overview: Sales -> Quotations
From here we can navigate to the quote we just created.
On this page, you can fully customize your quote request but for testing purposes let's just submit our quote request. After the quote has been submitted your customer will receive a proposal in his mailbox.
If your customer agrees to the proposal and clicks on "Proceed to checkout" the quote will be converted to regular order and your customer can follow the regular checkout.
Want to know more about other Cart2Quote features?
Please take a look at our feature comparison list.
https://www.cart2quote.com/magento2-quotation-module-editions.html