So, I think, overall, it’s dependent on what you yourself are comfortable with. But I will say that romance can add a lot to the story even if it is just a side-plot and having characters who are diverse and have romantic relationships can be a really good thing and add a lot of depth to your novel and characters.
I would say to start with addressing why you feel discomforted by the idea and work on that. Is it a sort of discomfort you may need therapy to address? (No judgement what-so-ever, this was my situation BIG TIME when I was a teenager. A lot of trauma in that regard so writing romantic relationships was super difficult for me because I had unaddressed trauma and fears about things like this). Are you worried that your inexperience with romantic relationships would lead to an unrealistic portrayal? If so, this is something you can work on easily (also struggled with this), you can submit your work to beta readers and prioritize the advice and observations given by people who have had relationships before (this can help you to understand others perspectives and lend you some idea as to their experience to make a more accurate portrayal), you could experiment with short stories about small romantic interactions and submit this for review, just consistently write topics like this until you become comfortable and grounded enough in this genre to continue.
Lots of people have inexperience with some form of relationship in their lives. Some authors, for example, who have never had a sibling write about siblings. It isn’t always 100% accurate to the experience, but they never get better at writing that dynamic until they’re able to receive feedback. Some authors have no experience with, say, losing a parent but they write stories about orphans and use the feedback submitted to them by people who’ve experienced great grief to improve themselves.
Truth is: nothing you write about will always be what you know. It’s more-so about practicing and giving your characters and stories what they need. If you feel a story needs zero romance, then it needs zero romance. If you feel like certain characters/themes would benefit from a romantic relationship, then it’s all about practice. I mean, look at your own works now. You never experienced an Ice-Age or had to break a curse by an ice-witch, but you find this idea fun to write about, compelling, that it creates an interesting story, and you improve that story along the way! Romance could be the same <3
Remember: writing is a craft. It takes a lot of time to be able to not only write but write about characters and people. It’s okay to be inexperienced in your life about certain topics and situations because, so long as you try, so long as you practice, then you are sure to produce something that is satisfactory to you. I believe in you <3