This has been asked and answered many, many times. Here are a few:

https://www.reddit.com/r/AskHistorians/comments/259vcd/how_much_evidence_is_there_for_a_historical_jesus/chf3t4j/?context=3

https://www.reddit.com/r/AskHistorians/comments/1zo99h/whats_the_best_evidence_that_jesus_did_or_did_not/cfvhpj5/

https://www.reddit.com/r/AskHistorians/comments/3ip60t/is_tacitus_the_main_reason_historians_accept/cuiuf1i/

If those threads and their related discussions do not satisfy you, feel free to ask again.