ACF repeater to upload images take too much resource

Hi:
I am using ACF repeater. I use repeater as steps creator and allow users to upload images for explain steps in the repeater.
I face the 502 bad gateway if upload too many images at one time.
I don’t want users can view the media library so I set the image Uploader type of Repeater to ‘Browser’.

Is there any way that I can upload image to database every time while user choose which image to upload in every steps?
Then we don’t have to wait user click “Submit” to upload image at once.
Or can we have a way to upload images one by one but not at once after click “Submit”?`

Thank you!!!