Hey there,
Thanks for reaching out to Apple Support Communities. I understand your iPhone is stuck in a boot loop, showing a low battery alert, and not being recognized by your computer. I’ll be happy to help with this.
For the issue with your iPhone not being recognized by your computer, go through the steps in this link:
If your computer doesn't recognize your iPhone, iPad, or iPod
Once you do that, go through the steps in this link and see if you can get your iPhone working as expected:
If your iPhone, iPad, or iPod touch won't turn on or is frozen
If that doesn't help, you'll want to reach out to Apple Support at the following link to look further into this with you as your device may need service:
Contact Apple Support
Best of luck.