OP, you sound lovely. You come across as a progressive modern woman who is kind, affectionate, caring and thoughtful about everyone. I understand where you're coming from and how hard it must be for you. I have extremely orthodox in-laws as well, and I feel by marrying into the wrong family, I've gone backwards in life.
I want you to take small steps, and lots of long breaths in between. We need to help you find a solution to your problem, let's face it, it's very difficult trying to change such rooted mindsets. I'm wondering if there's anyone at all, an elder cousin perhaps, someone who's well respected in the family and who you could confide in about your family. That person should be trustworthy and be able to slowly change your parent's thinking so that they learn to become more accepting of your boyfriend.
I'd also suggest your bf learn some Punjabi (a few words), a bit about the culture, anything that may help break the ice. At the same time request your parents to hear you out once, have an in-depth conversation about what you'd like to do in life, why you've chosen to marry your partner, cite some examples of successful interfaith marriages that have taken place, basically try to build their confidence so that they slowly become accepting and open to the idea of you two being together.
Are there any movies they could watch that depict similar love stories that end well? Bend it like Beckham perhaps? Open their mindset, this will take time, but promise you will never do anything that will bring shame to the family and marrying your bf is not shameful, many people get married outside their community and it's perfectly ok. Win them with kindness and love, if you can, I really do hope it works out.
I'm rooting for you OP, I pray things work out well for you and there's a happily ever after🙏