Hybrid bike? What kind of bike for a casual, petite rider

Hi all! I’m new to biking and honestly don’t know much. I currently have an old cheapo bike from target I got over 15 years ago in middle school. it was great but it has so many issues and am looking to upgrade. I’m mostly using it on our local walking/bike paths (so a mix of paved road, sidewalk and some very smooth pavers and pretty flat). I also have some issues with rounded shoulders so I’m looking at a more upright seating position. I’m just a casual rider trying to find alternative ways to get some exercise in and be outdoors. I’m also a short woman ( 5ft1 ) and 180lbs. Anyone have advice on what type of bike I should look for? I don’t want to spend a lot either, preferably under 300, but willing to do more if it’s worth it