can we define custom time out for each callout in salesforce?

Hi Suraj

The default timeout is 10 seconds. A custom timeout can be defined for each callout. The minimum is 1 millisecond and the maximum is 120,000 milliseconds.

For more information you can refer to this link:https://developer.salesforce.com/docs/atlas.en-us.apexcode.meta/apexcode/apex_callouts_timeouts.htm

Hope it may helps: