RAZER PHONE 2 CHARGING UP TO 100%

I have seen a lot of lithium-ion battery threads on how to make it have a longer lifespan but I just would like to hear it from all your experiences and as well as Razer's support team. Is it safe to keep my phone charged up to 100% from time to time? as well as use up the battery until it goes down to 10 to 5% before charging it? cause I'm feeling like my phone battery consumption is quite fast, playing games on 120hz for 4hrs and my RAZER Phone 2 battery goes down from 90 to 10% Also there was this one time when I was watching YouTube videos and I fell asleep for 3-4hrs I woke up and noticed my phone was extremely warm to touch. Please let me know what are your thoughts about this.