I need to send http request from different IPs in jmeter. As of the Number of Threads, for each thread the request has to be made from different IPs. How can I do it.
Source address input under "Advanced" tab of the HTTP Request sampler where you can specify the source IP address for the request.
If you need to use multiple ones, you can put a JMeter Variable there and populate its value via i.e. CSV Data Set Config
Remember that the IP address must be either "real" IP address associated with the physical network card or a "virtual IP address", you cannot put a random arbitrary IP addres there.
See Using IP Spoofing to Simulate Requests from Different IP Addresses with JMeter guide for more detailed description, configuration instructions and demo.