I don't understand. If you are an atheist, why would you want to refute things he raises from the Bible, which as an atheist carries no authority.
If you want to have a comeback, it is a futile mission, but realise that he has cherrypicked a few scriptures, out of context and misapplied. Here are some articles that show how.
"only those who invoke the name of Jehova will be saved"
Jehovah never appears in the New Testament. He is referring to Romans 10:13, which is a dishonest translation in the NWT. The name referred to is actually Jesus. jwfacts.com/watchtower/jehovah.php
....go preaching.
jwfacts.com/watchtower/preach.php
"even if you progess, keep doing this routine" ....go to meeting.
"encourage each other, and keep hands, you will receive gift for your work" ....paradise for preaching work.
"like the days of noah, people eating drinking, etc. people will not listen to god"....be in the arc of gods organization, or die.
"keep doing work till the End"....cant stop going to meeting and preaching till the end.
"look for god, and he will find you, leave god, and he will leave you forever"....
All of these apply equally to any Christian religion. The Watchtower is a doomsday religion, that has acted as a false prophet for over 100 years pronouncing specific dates for the end that never came true. See Deuteronomy 18:20-22 to find out how God feels about people making false predictions in his name. Therefore the Watchtower is not a religion worth considering as a place to gather for salvation, encouragement etc.