IMO this is an institutional problem at your workplace. I know my company's grown a ton and I've actually put in more hours ensuring one-on-one, high-touch onboarding time with all our new engineers so that they never feel unsupported and unknowing what the expectations are.

It's absolutely vital to recreate the same onboarding experience (seeing someone all day, being there whenever a question is asked, etc) virtually, and that means putting in the extra effort in making onesself available, checking in, and being proactive.