how to care for this dumb dumb and get him rehomed

i posted about this guy yesterday, whom i’m pretty certain was abandoned at our property (no neighbors around here have sheep or goats and my neighbor said people have left all sorts of animals at the turnaround by our house in the past). i lured him into the barn we have. he’s friendly ish but i’m very scared of him and that big ass horn. he’s also intact. when i opened the barn to check on him he stomped at me. i want to let him out to graze but i’m afraid he will escape through the fence and hurt my dog. should i tie him up in some way? should i leave him in the barn til i can find someone who wants him? sorry for such basic questions—i would never take on an animal like this without doing thorough research and i don’t know anything about sheep. feeling blindsided