If you click on the “Bunny Info” link at the top of the forum you will find a section on diet.
https://binkybunny.com/BUNNYINFO/tabid/53/CategoryID/2/PID/940/Default.aspx
I found the link for you.
It has good general info, and a link to a list of good veggies.
I go for whatever is suitable that is in season, because it tends to be cheaper at my local market. So until recently it was lots of kale, endive, and bok choy. I always have lots of carrot tops – my local market gives those away for free at every stall that sells carrots. So I get huge amounts of those each week and the rabbits love them. I usually add a herb to the mix, such as parsley, mint, or coriander.
As any guide will tell you, you want to go mostly for leafy greens that are low in oxalic acid. And then you can safely rotate a couple of veg such as spinach, that is higher in oxalic acid. Then you can top up with non leafy greens such as a small amount of carrot, capsicum, etc. And a small amount of fruit can be okay too – my rabbits will do anything for a piece of banana!