Why is my phone is very laggy and the new battery drain quickly

Hi @yohanpussella

Try turning off the Mobile data setting and check if performance improves.

This disconnects the phone from the internet but not from the phone network so you can still send/receive calls and SMS but not MMS (texts with pictures).

If performance improves or if you need constant data (internet) access as well, check which Apps have access to the internet and disable access to the ones that have it that you don't use all the time. Go to Settings → Apps → (select an App - not a system app) → Permissions and check.

What may be happening is that an App may be accessing the internet without you knowing and this impacts on the performance of the phone, especially if you're online at the same time.