Based on what you described, it leads me to think the internal component in the catalytic converter may have come loose and is plugging the exhaust when you try to accelerate. Did the check engine light turn on and stay on when the engine was running?
Do me a favor, take a look through this link, and let me know if it seems to mirror what you experience.
Also, if the check engine light is staying on while the engine is running, we need to scan the computer for diagnostic trouble codes. On this vehicle, the best thing to do is scan the can-bus system. CAN stands for controller area network. The network is what connects all the modules and computers together. Here is a video showing how that is done:
If that isn't an option, see if you can get your hands on a basic scan tool. Here is a quick video showing how to use one:
If the vehicle was drivable, most parts stores will do it free of charge. However, it doesn't sound that way. See if they will lend/rent one to you for use. If you do this, let me know the codes that are retrieved.
If you are unable to scan the system, let me know. We will try to go about things from a different angle. Also, if it is possible, record the rattling and upload it for me to hear.
Let me know,
Sunday, December 27th, 2020 AT 9:57 PM