I'm making a security camera using Raspberry Pi 3B+ . I want suitable battery to power my rpi. Is there any suitable battery pack that can power Rpi at the same time recharge the battery? I also found lipo rider pro. Can this serve the purpose? Is there any other solution. My Rpi will also be connected to Wi-Fi.
The feature you want is called pass-through charging by some. It's not typically incorporated in "power banks" because it's not good for the battery.
You may wish to consider a commercial UPS (examples) for this function. The battery is either charging (normal), or discharging if the AC power is disconnected.
Another commercial product that may accomplish this is a dual redundant power supply ([example])(https://www.jameco.com/Jameco/Products/ProdDS/2304391.pdf).
JoyIt has a product called StromPi, which is basically an USV particularly designed for the Raspberry Pi: https://joy-it.net/de/products/rb-strompi3. It can be equipped with an optional battery so that it likely does what you need.
Downside is that it needs a bit of configuration to be really usable and "ordinary" PI housings cannot be used with it, because of the additional height.