When I first moved to Seville, I was overwhelmed by the options to get around the city. The first couple weeks I walked most places, until I got enough confidence to get a bike membership. Now, I've almost mastered the bus route, and I often end up taking the bus so I am not sweaty from biking once I get to my destination. All my friends have different opinions on public transportation, but we are all agreed that it is amazing to have these options!
There are tons of ways depending on the time you have and the money you are willing to spend. Walking is a super-popular option for locals and also tourists, so they can take in the beautiful sights that Seville has to offer. There's also a bike network for which residents to pay a yearly membership; this fee allows them to use the bikes however they wish for 30 minutes every day. But it is also a little bit stressful because you have to find a place to drop off the bike near your destination. Similar to biking, there is a scooter option, but I have been way too scared to try riding one of these. The city has painted green lines on most of the sidewalks that are smooth for bikers, scooters and people in wheelchairs. This makes the city of Sevilla super-accessible for everyone!
There are also buses and metros that can bring you all over the city.