ANTICHEAT CHANGES IN 2021 WILL BREAK LoL PERMANENTLY, SEE BELOW.
In 2021, Riot plans to introduce a kernel-mode driver as part of their anticheat[1]. This is fundamentally incompatible with wine and will be the end of League on Linux (using a virtual machine with GPU passthrough may still be supported). If you are a new player considering picking up League, we recommend against it.
I recommend playing Dota available on Steam