Can someone help to find a way to find influencers to make up PR campaign?
First of all you need have a project that is worth investing in. You wont be able to find whales/advisors without any target in mind or working product at least. So you should work on the development of whatever you are aiming at first. Be it a new app or a new exchange or any new service. Again this needs to be something unique and the vision of the project creator should be such that it generates demand by itself.
Only after you have gained a certain amount of traction you would be able to execute a PR campaign/marketing campaign and then hope to see some good results. Following this you could contact venture capital firms and whales (maybe, Vitalik himself as well

) and they might be interested.