[Solved] Offline incriment in game

[Gyuszko]

feel free to search the forum a little bit, before you ask the same question, what somebody other have already asked.

How do I keep the game running even when the game is closed?

For example in (Idle Games) like “Realm Grinder”. You build 1 farm which generates 1 gold every second. You close the app and come back later with 1000 more gold. So the question being, I want to keep the game running, how do I do it? /As always thank you so much.