Mind you I am starting with nothing, but I am very handy with a computer, and electronics, and I have a 3D printer and a Foam Cutting CNC machine so I can make the board easy, but Not sure about the wings, or the stand, and While the electrics hook up will be the same as all my other R/C builds, it will be alot bigger, and water is new to me.
Also note I am not small, I currently weigh in at 300lbs
Welcome
I would recommend a few things to get you started out. 
Sign up for a efoil lesson with a good instructor to be sure you actually want to take up this activity. Not throwing any stones but your size is at the upper limit for this.
Do a bunch of reading as there are quite a number of very successful builds that are well documented.
Don’t post a question before using the search function of this site as your answer is likely already here.