Lots of questions on genital herpes

So my boyfriend and I want to have oral sex. I’d like to give him a blowjob but I have oral herpes and I don’t want to give him genital herpes. I have a lot of questions on the topic. If I don’t have a cold sore can I still give him genital herpes through a blowjob without a condom? Do I have to use a condom every time I give him a blowjob? Does a condom prevent him from getting genital herpes if I do have a cold sore? How often does someone with genital herpes get an outbreak?