[EliRivers]

Amongst other good answers, what's working well for my team in our new all-remote all-the-time era is deliberately assigning a different buddy from the team each day to the new starter, and making it clear that on this day it is a big part of the buddy's job to ensure that the new starter can achieve everything they should for that day on the day-by-day new starter checklist.

There is a timecode assigned for this, so the buddy isn't making time around other things; that day, this is a main part of their job.

On the first day, the principal task is a full clone and build of the principal software the new starter is working on. The second day is going through a full process of ticket assignment, working it, completing it (ticket carefully selected to be possible in a day and to exercise full process, so buddy has to introduce them to testers etc). And so on. Each day, a new face, a new buddy, and pretty soon they've met everyone on the team and had useful interaction completing real tasks.