What does fitness mean? Is it referring to physical fitness? Mental fitness? Something else?
What it means to be fit and how to stay fit can be different for everyone. As someone with a relatively sedentary lifestyle (aka couch potato), I feel I am at my most fit if I manage to be active for at least 10 minutes (usually fulfilled with my regular walks to the fridge), get a few minutes of fresh air/sun and manage to do a couple of things that help keep me sane (journaling, reading, so on).
I don’t always succeed at my version of staying fit but having recently learnt how negatively my body reacts to limited activity, I feel the need to rededicate myself to staying fit. Trial and error, that’s how things seem to work when you’re living in your twenties.