Long-term investing for a complete newbie.

Hello guys,

I am trying to save up to 50-60k per month and previously I made very bad financial decisions, now instead of wasting more money I will try to save up to 50k per month and I want to invest them long term, keep putting money in and forget, I heard that index funds are good of NBP and Meezan, I honestly have no idea about anything and I do not want to look at my funds actively at all, please guide thanks