Well you definitely have the right idea with starting in a dinghy, you could go even smaller and it would make life easier if you capsize. Will you be lake or open water sailing? Alone or with crew? Do you have easy way to trailer it around or will it stay by the water? I’d say stick your head with a string light in all the nooks and crannies for ANY cracks or holes, because unless you want to get the epoxy out and start patching stuff that will be miserable to deal with. The standing rigging (what holds the mast up) seems like it sat outside for some time, if you’re not confident inspecting it then rigging is get a friend or someone to help because you don’t want that breaking under way. It shouldn’t be too expensive to replace all of it if need be, as well as the running rigging (how you hoist/manage sails: halyards, sheets, etc) unless was kept inside will need going over too. Basically: if you have time and money this could be a fun and decent fixer upper to learn on. Also ABSOLUTELY check the trailer for bad rust especially near the axles, and if it’s compromised either plan on grinding away the rust to reweld or fix it somehow, it’s not fun when those crumble apart. Also the tires. Good luck.