hi krishna,
Business Process
What is a Business Process?
•Allows you to track separate sales, support, and lead lifecycles across different divisions, groups, or markets

Available Business Processes:

--> Sales Processes - Create different sales processes that include some or all of the picklist values available for the Opportunity Stage field
--> Support Processes - Create different support processes that include some or all of the picklist values available for the Case Status field
--> Lead Processes - Create different lead processes that include some or all of the picklist values available for the Lead Status field
--> Solution Processes - Create different solution processes that include some or all of the picklist values available for the Solution Status field

Business Process Examples

Lead Processes:
--Cold Call
--3rd Party telesales companies
--Leads generated via campaigns
--Leads generated via a registration form
Opportunities Sales Processes:
--Miller Heiman/ Solution Selling Methodology
--Inside Sales vs. Outside Sales
--New business vs. Existing Business (Up selling)
Case Processes:
--Customer Inquiries
--Internal Requests
--Billing inquiries
Solutions Processes:
--Internal vs. Public Knowledge Base
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Sales Process is mandatory for creating Record Type in Opportuity. Sales Process is used to create and maintain the Sales Processes used within our organization. A Sales Process contains the Stages an Opportunity follows through its sales cycle.

In order to create Sales Process, follow the below steps
1. Go to App Setup --> Customize --> Opportunity --> Sales Processes.
2. Click "New" button.
3. Enter the Sales Process name and click "Save" button.
4. Select the required Stage values and click "Save" button.
5. Now create a Record Type.
6. Select the Sales process in Record Type creation and save the Record Type.

Please check below post for screen shot
1) http://www.infallibletechie.com/2013/04/sales-processes-in-opportunity-in.html
2) https://certifiedondemand.com/salesforce-com-certified-administrator/sales-cloud/sales-processes-and-opportunity-fields-in-salesforce-how-does-it-all-fit-together/

I will recomment you please check below trailhead module for more information
1) https://developer.salesforce.com/trailhead/en/admin_intro_opptys_leads/admin_intro_opptys_leads_opportunities

this is taken from the link
https://developer.salesforce.com/forums/?id=906F0000000fxinIAA

Please let me know if it helps
thanks