According to the [guide|27316|iFixit guide], you need to calibrate your battery before using it by allowing it to drain overnight, then charging it to 100% and draining it again until your MacBook Pro shuts down automatically. Then you can charge it again and use it normally, However since it’s not being recognized at all, you should reset your MacBook Pro’s SMC (Also found on the iFixit Guide). You can learn how to do this here: https://support.apple.com/en-gb/HT201295
Good luck!
