If you have a fenced yard, put it out on a harness (not a collar) and a clothesline. I had a semi-feral cat that was not happy at first, but quickly came to appreciate the opportunity to go out on the line. Anchor the line in the middle of the yard, short enough so it can’t hang itself over any fences, and provide shade and some water if you are going to leave it out more than an hour or so at a time. Provide it something to hide in, as well.
No fence? Put it out only when you can supervise.
Otherwise, make it into a house cat. The cat will punish you, but it’s better than losing your kitty.
I would not put a cat on a line unless it was fenced in - a great BIG fence. My sister had a cat that was hit by a car. Her next cat she decided to protect from the same fate by tying it on a string so that it could enjoy a deck (up a long flight of stairs). Somehow 3 dogs got into the yard, ran up the stairs & eviscerated the cat.
Your cat has to be able to escape or get shelter if it’s outside. Best option is still becoming an indoor kitty.