I think you would get a lot more from a video than what anyone could post here. There are ton’s of them but I think this one (link below) is the best Ive seen (except for the red spot putty) to demonstrate the process. As Dale has explained there is some skill involved. Some pick it up right away. Others never do. Another option is to leave off the paint altogether. Tubs
Link – https://youtu.be/T4VshJmCCrU?si=_Qqt2n0peQTX-biF
A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.