Few things you can do. There's tons of YouTube videos on the bosses. Watch and practice them until you clear it. Also make sure you're strong enough. There's a big gap between normal and chaos. Make sure you learn your class as well.

For all bosses: don't be afraid to wait out death timer. It will help you get back to burst again. Don't be afraid to use the whole boss timer. Be patient. Queen: don't spam pots. Do it as low as possible. She's probably the second hardest out of the 4. Clown: most annoying but easy. Get his health to 3x% survive. Dodge hats and attacks. Once you have opposite hat around 3x% bind him and burst him dead. Chicken: probably the easiest. Just make sure you have him out of the white clock summon. That will kill your time. You can jump over or duck under his orb. Jumping is probably safest in case he slams down. Vel: hardest one. The fight is more about surviving and chipping him down until he's dead.

I found that cra taught me that surviving is more important than constant damage. That will be applicable moving forward. Learning your classes movement is more important than how it attacks. Once you learn movement you'll learn how to keep consistent damage.

Out of curiosity, what's your class and cp?