If you're already doing something like this or don't think you'll be able to, I'd suggest talking to your teachers and seeing if they can extend deadlines or help you find a solution as they're there to help!
I only finished my BTEC in 2018, but if I remember rightly, for coursework you will be given a sheet and you have to meet certain requirement to get P, M or D. Follow coursework guidance as much as you can and stick to that. Don’t over think it and try to only do what is asked of you. With my BTEC we were allowed a second chance with our coursework if we missed something and were allowed to resubmit it. If worse comes to worse you can always do this! Don’t be afraid to ask the teachers, that’s what they’re there for and they want to help you understand as best as they can.
Start coursework straight away so you’re given yourself enough time if you’re struggling. Stay behind after the class and ask the teachers. Type particular questions in online and get some ideas if you’re really stuck. I remember finding lots of answers and ideas online and that would give me a good starting point. Right down a few ideas for each part and follow them to give yourself ideas so you never get lost. You can do it! Don’t doubt yourself.