The answer to your second question is that Jews don’t expect non-Jews to follow the Mosaic Law (Torah Law) in all its details and complexities. Torah applies only to Jews, who carry a particular responsibility–due to G-d’s choosing rather than any special merit on the Jewish people’s part–as a priest people who are supposed to set and maintain an example of moral behavior for the nations of the world to emulate. Needless to say, one can never be perfect in practicing that behavior, but one does the best one can. However, we do expect you to follow the seven laws of Noah for the purpose of leading a moral life.
The answer to the first question, for me, is that I’m already aware of many of the dogma and doctrines in Christianity and, in particular, Catholicism. If the purpose is evangelism, then you might lead by the example of your faith and charity.