Subflow allows us to embed an existing Flow into another Flow. You can use Subflow input and output assignments to transfer the data between the master Flow and the referenced Flow, whereas the Wait element can only be used in autolaunched Flow to create a time-dependent action, for example, for sending an e-mail to the Opportunity owner after 10 days of Opportunity close date. To understand Subflow, we have to create a master Flow first.
A business scenario: Sara Bareilles is working as a system administrator in Universal Container. She wants to use Flow to create an Opportunity. Set the Opportunity fields according to the following requirements:
Close date is today plus 120 days
Opportunity name is the same as the account name
Map the account ID with the Opportunity account name
Stage is prospecting