Months ago, I accepted an offer via Discord to build a website. Since I would enter on a job on web development, I accepted (the project is no way related to my job).
My skills are not the best (~6 months) so I was assigned with a full-stack web developer so we could work together on the project.
I took this as a personal challenge and because I could ask for help, it would be a pleasant experience.
However, in the last couple of months I get drained out when I get out of my full-time job so there is little time/patience to do this extra job.
I'm, obviously, delaying this project with my lack of work and I don't wanna to affect the team as well so I'm thinking of leaving this big project but I still want to be on the developer team but probably with smaller tasks (maintaning code, etc..).
This will have some impact on the manager of the project.
How can I say to him that I'm not capable of doing this big task (building all the frontpage) but I'm able to do smaller ones and I don't want to leave his team?
I also want to highlight that this project is voluntary.
Update: Sadly, this project I was talking about was shutdown(ed). I thank everyone for helping out on my question.
I found this question while asking, it's certainly interesting but doesn't apply that much to my question.