Pi Pico and usb battery pack for UPS

I would like to per pos this ideal!
I don’t have the skills to do what I would like to but this gives me an ideal. Could I use the Pi Pico and a usb battery pack as a U.P.S for my home assistant pi? To keep the battery good. I would like to have it stop charging when it hits 70-75%. then charge again if it drops to 40-30%. If the power to my home assistant get cut it will send a safe shutdown command and keep it powered tell the battery dies or the power comes back. I know that there is a way to have home assistant track the level of a battery for my phone and tablet.
Low-dropout or LDO Regulator MCP1700-3302E
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