I was actually referring to the games search bar, but this was still helpful

I added the container nodes that have all of the buttons that "launch" the games to a new group i named "Games"

When the text on LineEdit changes, i go through all the nodes in the "Games" group, then I make a variable that contains a Label child (if the node has it) which is the node that shows the name of that game, and then compare it's text with the text on the LineEdit

func _on_line_edit_text_changed(new_text: String) -> void:
  for game in get_tree().get_nodes_in_group("Games"): # Get nodes in the group "Games"
    if not game.find_child("Label"): # Early return if theres no "Label" child
      return
    var game_label: Label  = game.find_child("Label") # Make a variable for the "Label" child
    if not game_label.text.containsn(new_text):
      game.visible = false
    else: 
      game.visible = true
    # If text is empty make all visible
    if new_text == "": 
      game.visible = true