How to specify Default Level Blueprint?

Thanks for the answer Nawrot, now I have a clear idea about the approach.

May I ask what parent class did you use for the Spawner? I guess a simple Actor will do the job, just want to be sure.

Also, if I implement my ‘random spawnpoint selection system’ in the Game Mode, I just use a Level Loaded Event and connect each of my levels to the spawpoint system?

Is this seems correct or am I missing something?