A couple of years ago I hiked parts of the Ostkustleden with some friends around Eastern. It’s a beautiful, easy and very relaxed trail leading you through the nature of southern Sweden.
The length is around 150 km and it can be easily done in 8 days with multiple huts on the trail that can be used for shelter. Since it’s basically a circle trail, you end up where you started making arrival & departure a relatively easy task. There were buses from Stockholm heading south - I’m pretty sure they exist today as well.
Although it’s hard to get lost on the trail, you can find some GPS coordinates here.