Can't connect my "Cast to" node to "Enhanced Input Local player subsystem"

Hi!

I’m new to UE5 and I’m trying to create a graph so the player can switch from one character menu to the next in the character UI menu. So, not in game. I found tons of videos about how to switch character in game, but not in the menu itself.
The training I was following is on UE4, but as you know, the mapping changed, meaning what I built previously doesn’t work without the “Enhanced input local player subsystem” node, and the “Add mapping context” one.

My problem is that I’m not sure where to connect them in the attached path.
And when I try to just attach them to “Cast to BP_GameInstance”, it’s not working, as it says it’s not compatible, but I don’t understand why.

Could you please point what I’m doing wrong?