Two factor authentication is a security process in which the user provides two means of identification, one of which is typically a normal user credential and the other of which is typically something memorized, such as a security code.

1. Two Factor Authentication
Using Login Flows:

2. Two Factor Authentication
Two-factor authentication is a security process in which the user
provides two means of identification, one of which is typically a
normal user credential and the other of which is typically
something memorized, such as a security code. You can enable
Two Factor Authentication for users by adding “Two-Factor
Authentication for User Interface Logins” permission through a
Profile or a Permission Sets.

3. Login Flows
A login flow provides the ability to build custom business processes and
invoke them as users log in. This lets you integrate a custom process with
the Salesforce authentication engine, as well as the ability for users to
participate in the authentication decision process during the login process.
To create a Login Flow, follow the below instructions,
1) Click on Name | Setup | Administer | Security Controls | Login Flows
2) Click on the New button
3) Enter the Login Flow Name, Select the flow, User license and Profile, it
will look like the below screenshot.

5. Flow:
It is an application that automates a process by collecting, updating, editing,
and creating Salesforce data. Flows can execute logic, interact with the
Salesforce database, call Apex classes, and guide users through screens for
collecting and updating data. Most often, flows are built by using the Cloud
Flow Designer.

7. To test this application, follow the below steps:
1. Login into community through User who have same profile that you have used in
Login Flow, In my case it’s Partner Community User Clone. After Successful login,
you will receive an email, it will look like the below screenshot.

8. 2. Enter your Security Code onto the screen input field (i.e. Token) and click on the
Button, as shown in the following screenshot

9. Thank You