The episode table
Every season has its own page with a table: the episode number, the title and the date it first aired. The Good Place has four such pages, one for each season.
The 1x15 style
On the home page, an entry such as 3x7 means season 3, episode 7. The link opens the season page at that row.
Marking your place
Tick the episode you reached and SeriesStream keeps the mark in this browser. Your saved place then shows on My List beside the series.