Stuck at Country Level 1

I am completely stuck at Country Level 1 at Chapter 2 (Barre Chords 5th String Root).
I am not be able to bend my ring finger in order to block the chords: I even tried to use it without the index, only blocking the three chords but I never had a consistent sound from the chords and, beside that it hurts a lot!
I can make barres with 6th chords but I can't bend that finger like that.

Beside, I only have an acoustic guitar, so I can't go on! 😢

Sorry for you frustration!  Here are some potential options.

Use a power chord verse for each chord.  Just play the root & 5th.  For example E5 instead of the full E major barre chord.

|--------------|
|--------------|
|--------------|
|---9----------|
|---7----------|
|--------------|

Also consider that this is electric guitar material.  So you could just skip it and move forward in the course until you find something that interests you and, or uses acoustic guitar.  There is plenty of material in the Country course that focuses solely on acoustic.

If you don't have an electric & don't intend to get one, then just switch to the Acoustic course.  It might be more suited to your musical goals.

https://www.guitartricks.com/course/acoustic1

Whichever option you decide works best for you, keep practicing & playing whatever you can!  Best of success!

Thanks for the info, you made my day.