You've read the manga?
What platforms do you use - Android, IOS, Linux, Windows?
MacOS?
I use Android/Linux so I'm not sure what options you have for IOS manga readers.
Whatever app you use, set the format to webtoon and enjoy the fuck out of Solo Leveling.
I warn you it's highly addictive and I take no responsibility for you ditching your normal daily life while you read it.
I found the Tower of God anime very confusing from a continuity perspective. Kinda ruined my enjoyment.
Anyway, let me know how the install/download goes. I hope it works out.