Let your parents know and get the right support. ADHD coach or educational therapist to help you organise and prioritize.
Reach out to each teacher and schedule one on one meetings. share your challenges, ask for extensions on all late assignments.
Break up large assignments into bite-size, manageable chunks, set a timer and work in 25-minute blocks with 5-minute breaks, repeat.
Turn off and get rid of all distractions, turn off notifications, and just start! When the pressure is on, just start, and you will feel better.
Order yourself a calendar. I recommend this calendar https://products.orderoochaos.com/collections/academic-planners
I am a mother of a 7th grader who has similar issues.
You can do it!