I have a load (more specifically a Raspberry Pi 3 B) which requires a voltage of 5.2V and needs around 2-3A current. It should be powered by a LiPo battery with a capacity of 6000 mAh. In addition to that, the battery should be chargeable with a power supply (in less than 6 hours) and at the same time power the load.
As far as I've understood I first need a DC-DC booster to reach 5.2V but also a charger module that is safe. I cannot build such a module from scratch because LiPo powering can be quite dangerous and I'm not a battery expert. But it seems like there is not such a module to buy online, especially when it comes to the 5.2V/2-3A requirements of the load.
Now my question is: Is there actually a way to achieve all this? And if yes, which components do I need to build a charger with an integrated booster?