If you want to explore how malware works for a career in cybersecurity, avoid live malware on your primary machine. Instead: Use Sandbox Environments:
This article is provided for educational and cybersecurity defense purposes only. NJrat (NjRat) is a Remote Access Trojan (RAT) classified as malware. Unauthorized access, distribution, or use of this tool against systems you do not own is illegal in most jurisdictions (including the Computer Fraud and Abuse Act in the US and the Computer Misuse Act in the UK). The author does not endorse malicious activity.
If you're interested in cybersecurity and RATs for educational purposes, there are legitimate tools like TeamViewer, AnyDesk, or Chrome Remote Desktop that offer remote access capabilities legally and ethically.