Hi. Appears that you have complete tear in your acl Ligament that means you might need surgery if any instability symptoms are present. Your stiffness and weakness in muscle are due to pain and immobilisation which will recover gradually depending how good you follow the rehabilitation protocol. Meniscus tear might heal or it may require repair if your pain persists.
Next Steps
Do good rehabilitation. Consider consulting a arthroscopic surgeon to guide you through.
Health Tips
No sports activities. No sitting cross legged, squatting or stairs climbing.