Locked Jaw/ Blow jobs

I have lock jaw really bad and my mouth does not open far at allll. I can’t even fit a lollipop in my mouth😖 my boyfriend and I have been together for four months now and I feel soo bad that I can’t give him head. He’s super understanding and never says anything about it but I feel bad. We have great sex but I just want to please him more than sex. I feel like I’m not very good at hand jobs although I do think I’ve gotten better sometimes when I’m giving him handys but can you ladies give me any tips to please him.😩 also he is also the first person I’ve ever been sexually involved with so all the pointers would be great!! TIA