How to connect multiple external hard drives to my mac book pro?

my macbook is 16" macbook pro 2019 version.

I am using a usbc adapter to connect my external drives because they only have usb connector.

It's Ok to connect with the one external hard which I am using for Backing up.

When I connect one more external hard which I want to keep all photo files, it keep the macbook eject all the external hard drives.

There is this message when I tried to connect my second external hard.

USB Accessroies Disabled

Unplug the accessory using too much

power to re-enable USB devices.

My photo files are pretty big, so can't save direct to the labtop or in the same drive as I use for backing up. so I really need to connect 2 external hard drives to my macbook

Please help me!