You can still find vintage, all metal, mechanical sewing machines for cheap or free. Some are just basic stitches. Some take cams to let you do fancier stitches.
I personally love my very basic Kenmore 148.19370 (a.k.a. 1937) but there are many other vintage Kenmores (and other brands) that fit what you describe. I understand from a vintage Kenmore FB group I'm in that models 1914 and 1941 are very good. You might need to clean it inside and out to get one working it's best or you might luck into one that works perfectly and just needs regular oil and cleaning (like I did with my vintage machines).
Newer isn't always better. Vintage, all metal machines are solid machines. I'd take one of them over a computerized new machine any day. (No offense to anyone that prefers the computerized machines.)
There's a woman that buys, cleans, repairs then sells vintage machines. She posts videos of her machines on youtube and talks about their features and accessories. I found her videos very informative when I was trying to learn more about my machines that I got elsewhere. You might find her videos helpful, too, to do a keyword search for the model if you find one elsewhere that interests you. You could learn more about it from her. I've never bought from her (and don't know her) but she seems to have a good reputation. She's Rayna Moran, a.k.a. niftythriftygirl. Here's a link to her youtube channel.
https://www.youtube.com/channel/UCQt...rW9QwJn9Rb_NlA