Using iPhone while charging

So I got my hand on my new iPhone 8plus And I feel noticeable battery drain (yeah the 8plus battery is smaller than 7plus what I heard) And get to the question I found on the forum which some said using a phone while charging will damage the battery and extra battery wears because battery need to receive power in put and output it And the others one said if you charge your phone while using will keep your charge cycle and help phone battery stay longer because when you use a phone while charge the app(s) will use the power of the charger and left enough amount for the battery to charge Since both answer make sense I have to repost and ask the community Does it good or bad to use my phone when charging ? And if it does can I still do it sometimes ? My first time in the forum Pardon my English Best regards, Sambat,