Ok thanks for the comments. I updated the cave entrance. Also made the cliff at the bottom continue. Tried changing the grass to a more suitable color. Although, I think it is too eyestraining.
Actually i think the shape of the hole is fine, it's the crispness of it. try not ot use such sharp edges when describing volumes. Quick example.
Keep it up! This is a great start :).
Pretty good for a first try. Try not to use such smooth edges, the hole will probably never be that round.
The cavern entrance is too simple, just a circle hole. Try to fit it in letting its borders to follow the rock texture you have. Don't know if I expressed myself correctly, hope this help. :) The rest is well made.
nice look ... for me is a bit unfinished because it's very empty, but look nice. hope to see more :)