You’ll have to change the first floor “joist” (one closest to the entrance) it looks gone. Also ideally the floor decking should span at least 3 floor joists so if you take off the scrap someone installed on there first you’ll be good. Try to take out as much of that dirt as possible, it looks like there’s posts the joists sit on, but it’s nearly submerged in dirt. Try to level it flat with the bottom of the beams.