I just had meniscus repair surgery. How long am waiting until I can walk safely on it?

It depends. Depending on the type of repair, your surgeon may protect your weightbearing and your activities to maximize healing. If part of the torn meniscus was removed, you would be allowed to walk as soon as you feel able. However, if the torn meniscus was repaired with sutures, then you might need to use crutches (partial weightbearing) for 4-6 weeks and gradually resume walking. Check with the doc.
Depends. Follow your surgeon's instructions because you want to give your meniscus the best opportunity to heal. Usually, this is 4-6 wks of non-weight bearing, but it depends on the size of the repair and its location.