I’d highly suggest checking out some of the videos on the HowToADHD Youtube channel. Search in the channel for “procrastination,” “tasks,” or “getting things done.” There’s no one solution.
Also, decide why these things are important to you. Are they important to you? Do you just want to finish them to feel a sense of accomplishment? Do you need to complete them for a certain job or person?
Not all tasks have to be done. We sometimes put pressure on ourselves because we feel they do, though.
Definitely check out the channel. There’s lots of options for tips and tricks that are worth trying out. Maybe you’ve tried them all before, but people share stuff in the comments sections of the videos that work too.