I am using Selenium to get some results using Google search. The program is implemented in Java. I search for some keywords like allintitle:best smart pc. So when I use this keyword multiple times google is banning my IP. So I need to know how to prevent this issue? How can I search for a list of keywords without banning my IP? Is there any alternative way of using Selenium and Java to do that?
No, if you persist Google will ban you, you are breaking their Terms & Conditions, specifically:
5.3 You agree not to access (or attempt to access) any of the Services by any means other than through the interface that is provided by Google, unless you have been specifically allowed to do so in a separate agreement with Google. You specifically agree not to access (or attempt to access) any of the Services through any automated means (including use of scripts or web crawlers) and shall ensure that you comply with the instructions set out in any robots.txt file present on the Services.
If you are just trying to learn how to use Selenium I would suggest using something like The Internet (A group of learning resources for automation) instead.