Probably. Just because you can learn from google doesn’t mean it’s not skill. Most car trouble can be done that way- so is it ok on chol hamoed🤔
IMO, anything one can learn from a cursory Google search is not a maaseh uman. A maaseh uman is something that requires umnus, i.e., expertise/craftsmanship/professionalism/experience...
It's like comparing following a recipe in a cookbook to making a dish that only chefs can pull off.
Same re car repair: depends if it is simply following instructions or needs actual expertise.