How to multiple upload one by one instead of all at once?

Hi. Instead of having multiple upload files at once, I want the multiple upload to perform upload by one item then another until completed.

Expected behaviour:
Upload file 1 > Process Image > Success > Do something > Repeat process until finish.

The reason why I ask this is that, for multiple large files upload at once, this process utilises quite amount of server/hosting resource and I’ll get timeout error due to this. So I think my best bet is to perform multiple upload step by step. Help me figure out how to achieve it please…