Scraping different categories using different links through proxy
Assuming the proxy dictionary with duplicate keys is just a posting error, here are some of the things I think need to be addressed:


as usual, create a requests.Session() instance and re-use - this would not only allow to set headers and proxies once, but also improve performance
I would define headers as a constant or go even step further - rotate user agent strings as well - there is a fake-useragent project that would help
there is also this DRY principle violation - you are repeating cssselect() calls twice per element - in this case, it's not only the repetition but is also something that unnecessarily slows the HTML parsing down. Define a reusable function that would handle the problem:

def extract_field(root, selector, default=""):
    try:
        return root.cssselect(selector)[0].text.strip()
    except IndexError:
        return default



Here is the code with the above and other modifications applied:

import csv

import requests
from lxml.html import fromstring


def extract_field(root, selector, default=""):
    try:
        return root.cssselect(selector)[0].text.strip()
    except IndexError:
        return default


def crawl():
    proxy = {  # assuming is correct
        'https': 'https://188.166.154.140:8118',
        'https': 'https://198.52.44.130:53281',
        'https': 'https://46.101.2.115:8118'
    }

    with open("amazon.csv", 'r') as input_file, requests.Session() as session:
        session.headers = {'User-Agent': 'Mozilla/5.0'}
        session.proxies = proxy

        for entry in csv.DictReader(input_file):
            url = entry['Link']
            response = session.get(url)
            root = fromstring(response.text)

            name = extract_field(root, "#productTitle")
            star = extract_field(root, ".AverageCustomerReviews .a-icon-alt")
            count = extract_field(root, ".AverageCustomerReviews .totalReviewCount")

            print("Name: {}\nStar: {}\nCount: {}".format(name,star,count))


if __name__ == '__main__':
    crawl()