Writing the "Other" is fundamentally about empathy and doing your best to inhabit their context.
The first thing I'd do is identify what story you want to tell. And I don't mean what story as-it-relates to race. Simply your overall themes and purpose for the project.
Once you've done this, determine whether your theme is better suited to our world or another world. If it is our world, based on your premise, you have to deal with race
If it is an alternative world, consider whether your theme is served by imagining racism-to-not-exist or whether your theme is better served by saying something else about racism. The relation of racism to Theme/Purpose can be as simple as wanting to tell an inclusive story that POC can relate to.
Prejudice is such an expected part of human cultures and conflict, that it's fairly unrealistic not to have it, even in speculative works. Such a society would require pretty extensive changes and/or very special contexts to have minimized or abolished all forms of ethnic prejudice and the power imbalances that metastasize prejudice into Racism. A society without racism is even harder to engineer than a society without war.
If racism is something you are including, (And I generally advocate that people not ignore racism in fiction) the first thing to understand is that racism is omnipresent for black people in America. (I'm assuming your story is set in America or an American analog. If not, the rest of this feedback may need to be amended or discarded to fit your setting.)
And when I say omnipresent, I mean it. Nearly every single interaction we have, even with other people of color, is influenced by race.
Whether you cross the street. The feeling when you log onto Stack or social media. Going to see a doctor. Driving to work. Buying or using a ticket on public transportation. Everything. 24/7. Until you die.
This is not to say that it is conscious. But it is always, always, always there. And it will absolutely be there if your romance is interracial. Black people need to be incredibly selective about who we choose as interracial partners.
If we're getting personal, one of my absolute worst memories was turning to a partner in a long term relationship, feeling kind of low and angry and powerless after a race-inflected experience. The intimacy and connectedness of years can be blown up in a single moment of realizing exactly how different you are from an intimate partner. Race creates entirely different perceptions of the world and approaches to it. To seek a deep connection with someone who knows you, only to have it replaced with a gulf of racial misunderstanding is a pretty horrible experience.
It was an abject lesson that even decent, well-intentioned people can "not get it". It also etches in you the consequences of people "not getting it". Which can range from unpleasant to life-changing or dangerous. The people that "get it" are so few that you basically have to check folks on racial issues if you plan on having any kind of genuine interactions. It's pure self-preservation.
Because white supremacy is an omnipresent factor it creates a kind of "battle" mentality. Imagine its like an additional diagnostic that's always running in the background, alerting you to times and moments when we need to expect different treatment. For example, on the way to work yesterday morning, a cop-car was driving, slowly, next to me as I walked.
Were they checking me out? Don't know. I didn't make eye contact. But I noticed.
Should I take out my headphones? Who is around me and what are their demographics? If I'm stopped, how much irritation can I afford to express? If I make this turn, as usual, will that make me seem suspicious? Is the cop black? How much does that matter? How quickly should I produce ID? What happens if they somehow realize I have a pocketknife? Are the gloves in my pockets printing like a weapon?
Imagine that going through your head, in only a five second span. Now imagine that for more than five seconds. A minute. An hour. Two hours. Until lunch. During lunch. All day.
Welcome to being black.
Other things to bear in mind? Well, black folks' honesty on race is kind of an inverse bell-curve. On one end is low-intimacy/high-honesty, and on the other side is high-intimacy/high-honesty. With a huge dip in the middle. All those "black friends" who people think "are okay with XYZ"?
They're bull@#%&*&% you. If you're using us in some example in some conversation, there's a 90% chance we don't actually like whatever behavior you're discussing and are too polite to ask you to stop.
I could go on forever, but the bottom-line is:
Race and racial considerations have an omnipresent impact on our lives. It doesn't mean we change our outward behaviors in any way, but remember that idea of a "running diagnostic". That's the best way I can explain it.
If you feel unfit to the task of this character, I'd suggest soldiering on. Precisely because the mere act of asking this question makes you better equipped to write that character than like 90% of the non-black population
You passed my first 'check' LOL.
Best of luck.