I'm a yoga teacher. For years I told myself, "I can't do side plank." One day as I evolved, I said to myself, "Maybe I can." So I tried it. I can do side plank. I had never tried it because for years I told myself I couldn't do it. Big lesson learned! Now I am very wary of those times when I hear myself saying, "I can't..."
My brother (he's in Ohio, I'm in Kansas) has a medical condition that affects his ability to walk longer distances. It's extremely distressing for him, as he has always been very active. I believe I have some techniques and equipment that can significantly help him, plus he said, unprovoked by me, "I am going to beat this." I sent the equipment to him, and I'm making him videos (posted on youtube) to teach him how to use the techniques and equipment. Right away he started with "this is too complicated for me to learn." That's just another form of "I can't," and I called him on that bullshit immediately, encouraging him to not eliminate something that could vastly improve his condition just because he has to learn something new. I'm not letting him get away with any form of "I can't."
Listen to yourself. What joy, adventures, empowerment, creativity and learning are you denying yourself with "I can't"???