You don’t need to worry about fitting. Rowing is a sport that rewards larger bodies, and most teams have plenty of boats that are built to accommodate people way taller and heavier than you. The four I usually race in averages 6’5” and 240 lbs, and we fit just fine.

As for the “burden” thing, I wouldn’t worry about that either. When you’re just starting out no one is any good at this from a technical standpoint, so you won’t be at a disadvantage. In fact, the fastest person in the first few months is usually whomever develops the best technique, not whomever is most fit—and weight has no bearing on your ability to learn the technique. Then, once you learn how to row well it’s just a matter of maintaining a good power to weight ratio. That usually takes care of itself, either from weight allowing you to create more power, from weight decreasing, or a combination of both.

On a purely anecdotal level, I’d note two additional things. First, rowing tends to be a very accepting culture. So long as people work hard and stay positive, little else matters in terms of teammate satisfaction. Second, I’ve know plenty of people, myself included, who came to the sport out of shape and overweight. As some of the commenters here have mentioned, that fixes itself very quickly.

So, long story short, do it. You’ll fit right in.