I need help with my players.

So I (18) have been a DM for about 2 years now, and have played the game in total for about 4. I am currently running a campain with some friends (all around my age) based on Norse mythos, where the players are nominated to become this grand asgardian worior team and have to compete against other teams for the role. They had to go through 5 diffrent tryals all on the diffrent realms, all with a diffrent aspects to it. (Tryal of strength on asgard, tryal of endurance on nifilhime, tryal of defence on midguard, tryal of past and future on alfhime, and tryal of devotion on nidaviler.)

That is the main story of the campain so far but I feel as if my players don't care that much. Often times throughout the sessions my friends are joking and laughing together so much they can't hear me speak and have to ask "what's going on". They will often get sidetracked by something in the room, or just act overall insane while playing.

One time I had left some cards out next to the table we were playing at and they made up a card game on the spot and started playing it during the session.

My best friend is in this campain and is definitely the most experienced player besides me, and when I comes time to make a decision he is always making the decisions, and the others just blindly follow, not thinking for themselves.

At the end of the 4th tryal I had frigga give a criptic prophocy about my bbeg and the players. This guy has been behind all their struggles on the side and behind a big war that asgard is in the middle of, but he is hiding in the shadows. After I gave them the prophecy they haven't Evan talked about it in the last 4 sessions.

I have tried everything that I can think of.

I HEVALY used their backstorys that they made to make them want to engage with the world more. Like I incorporated several npc from eatch players background, I have included villages and wars that they cam up with and put in their backstorys

I thought it would be too linear if I had them just do the tryals, so i included downtime in-between the tryals. During this time i have helped them make a restaurant of their own to have as a source of income for them.

I have included all the realms for them to explore together and have city's on eatch one.

There are several diffeent shops on asgard for so meany diffrent things, all of witch have a diffrent atmosphere and theme.

I have an underground network on asgard run by loki, with more shops and places for quests for Magical items or money.

I have tried talking to them individually but all I get are "yah we can dile it down" or "we'll when you put a bunch of good friends in the same room they are gonna be a bit crazy"

This is why I need your help, I have no clue how to get them invested in the world as much as I am. I don't want to just kick them from the campain and start over, They are some of my best friends I have had for years. I have spent countless hours making the story, writing a cool villain, and a cool prophacy to introduce him, but it all feels in vane because they don't seem to evan care. It is verry exhausting to spend so much time making such a cool world for them and then feel like they don't evan care.

If you have a suggestion I would kindly take the help