How much does infertility leave cost?

Hello...
I have recently been considering taking a leave of absence for infertility treatment. I think I need to start IVF, but I'm very worried and conflicted about how to balance it with work.

First and foremost, I'm worried about the company. I want to take a maternity leave, but I don't know how to bring it up. How should I talk to my team leader... I wonder how others have mentioned it. Also, what will happen to my work during the leave, and will there be any disadvantages when I return to work later... These worries keep coming to mind.

I'm really worried about the cost. I heard that a single procedure costs several million won, but how much would I actually have to pay if I receive government support? To what extent is insurance coverage available... And if it succeeds on the first try, that's great, but what if I have to try multiple times? Then how much more would it cost... Thinking about all these things gives me a headache.
It's also vague...

And my mind is also very troubled. Since I'm getting older, I feel like I should start quickly, but when I actually try to start, I feel scared... I keep thinking, what if I fail? My husband says, "Take your time," but I feel like I'm the only one rushing, and that's also stressful.
Everyone around is just spreading rumors and hearsay...
I think the success rate will be higher if I feel at ease, but I keep just rushing ahead with this and that ㅠㅠ

How does everyone get through it... How do you work while receiving treatment... How do you prepare the expenses...
Please let me know if there is any helpful information...

Thank you.