Blow jobs

I recently started giving my boyfriend blowjobs. Its a new thing for me and it makes me really happy that he enjoys it so much. He keeps talking about swallowing. Sometimes its joking because he doesnt want to push anything other times its curiosity if I'd want to. I don't know what to do without choking or gagging if it tastes bad. I also don't get if it will really make it that much more enjoyable for him. Help!! Any tips or advice would be much appreciated.