toomuchtodo gave you some excellent advice:

Have you considered charging a dollar annually (like WhatsApp previously did) and seeing if current users will pay? If you’re out of funds, and have no seed round lined up, why not attempt to monetize immediately?

Also, have you explored if Amazon has any accelerator programs you’d qualify for to get some AWS credits to tide you over (paging jeffbarr).

$1 per year might not completely solve your cash flow problems, but it will bring some money in and give you some powerful evidence to help with your fundraising.

Amazon has accelerators programs I have one right now I was accepted to Startup school of YCombinator, but the credits are only 1000 that is enough only for 2 month I need at least one year to grow a lot and to get investment from a venture capital fund So, I will try to charge 1 or 2 dollar maybe by month , so I could pay the servers

It's your startup so do what you think is best, but at $1 - $2 a month, you'll lose a massive number of users. Then, I don't know if your app will be worth $1 - $2 a month (or a year).

How can you save money on hosting?

OP could move from AWS to bare metal, and trade some resiliency for runway.

That's a good idea. I bet that OP could save quite a bit running something on bare metal. And, if they are looking to extend their runway, maybe a specific ask like "Can anyone hook me up with $x months on $provider?" would have more luck than a generic 'looking for co-founders.'