Taking public transportation in Maryland near DC?

I’m moving in a few days and won’t have my car with me for a month. I also have never ridden any public transportation before. I found the bus route from my apartment to work. It says it’s a 11 minute ride from my bus stop to the bus stop next to work. It also runs every 15 minutes. I start work at 7am but need to make sure I’m on time. I also know traffic is terrible in Maryland. If I take the 6:16 bus it says I will arrive at 6:27. Does this tend to be very accurate?

Also the walk from my apartment to the bus stop is a 22 minute walk. I read I can take a bike on the bus. Is this fairly easy to do? I just toss it on the racks that’s behind the bus? I’m still debating if I want to just walk that 22 minutes every day or get a bike. This will also only be for a month.