Peugeot Milano, old steel

Looks like a great candidate for a rebuild and learning experience.

The sticker on the downtube clearly says "CroMo" meaning an alloy of steel with trace amounts of chromium, manganese and molybdenum. Either way its still steel, but a different alloy.

I have a concern in the stem - it looks to be very far out of the threaded headset, so do check that it is installed far enough. You should not see any trace of the "minimum insert" marking.

Also, someone has fitted the saddle backward and then rotated the seat post which is causing the extreme up-angle. Flip the saddle, rotate seatpost, and it will be a lot more comfortable.

Depending on the age, you may need new brake pads and/or tyres. But the chain may come back with some flexing and lubrication.

I'd spend as little as possible to make it work, then get some distance on it, and see what still needs work if anything.

As for age, its a tough one. The slight dropped seat stay is generally quite a modern feature, but the brand, rake of fork, canti brakes all call out 80s touring bike but with a replacement stem and bar. Its an intriguing bike and will be a nice ride when done, assuming its a good fit for you.