Very first question. Any Christians on this site?

I'm new here so I need a bit of guidance on how to use the site. I have fathomed out the basics of how I put a picture and name on which is Sweet Jesus. Not my name obviously, haha! If you are offended please don't be I'm just working it out. My question is, I want to evangelise, can I do that because my Pastor said that I would be good doing this.