Can I create an automatic quotation for my customers?

Sure you can.
a quote / Quoting / Quotation form enables you to collect your clients' information and automatically create a custom quote based on it. 
This is a great use case which replaces a sales person.

Creating an automatic quote:
This is really simple to do, quite frankly, using conditional logic and calculated fields.
Calculated field/s
The calculated field uses the data entered in the form within a mathematical formula you configure and then produces an automated estimate.
As for the conditional logic: If there is more than one possible flow to get a quote, you can add a few calculated fields that contain different formulas and use the conditional logic to route different data to a different calculated field.
for example: Let's say you are selling 2 products :Pro A and Pro B,  They have the same price of 50$, but, there is a 20% discount on Pro A and a 50% discount on Pro B. In this case you would need one calculated field that calculates Pro A price, quantity and 20% discount rate. and another 
calculated field for the Pro B price, quantity and 50% discount.
Read all about using the calculated field for calculations
Read about using the conditional logic

Providing the quote
Once the quote is calculated all that's left is to hand it out to your customer. There are many options to do this - here are some:
- You can display the quote inside the form using a string type calculated field.
- You can also display the quote in a custom thank you message after the form is submitted.
- You can create a custom email - giving your customer a carbon copy of the quote.
- You can create a PDF document based on the data entered in the form and have it sent to the customer.
and you can add a Payment integration to your form and have your customer continue to an online purchase right after showing him the quote in the form.