My mother sewed a good bit as I was growing up but I didn't. She did a good bit of upholstery work too.
My father had been a shoe repairman for the first 18 years of working and did a lot of leather sewing but that was before I was born. He had kept one old Singer patching machine and I did use to help him when repairing the feeder canvas on our old combines over my early years.
Since I still have my shoe repair shop (not in use) I have a number of sewing options. I owned a shoe repair shop (along with several other businesses) for over 20 years. I had the store for 25 years. I have 5 sole stitchers, 3 are curved needle machines and 1 is a straight needle and another is a chain-stitch McKay stitcher (a type, not a brand) and I have 2 Singer patching machines along with a flat-bed machine. That doesn't count my wife's machine.
Lots of sewing going on in a shoe repair shop.

You do a lot of leather repairs and I installed a lot of boot zippers (one of my least favorite jobs.
My wife normally only does patching on my jeans and hemming. During the 20 years we had the shoe shop though she did gradually start doing some simple sewing repairs on shoes and must have repaired a half zillion load-binding straps for a couple of local trucking companies.
I have done a little upholstery work and made some specialty covers over the years but they tend to be too time heavy for what you can get people to pay.
I generally enjoyed the shoe repair and leather work over the years. I fully intended to operate a retirement shoe repair shop and gathered a shop full of equipment, finally settled on a location here on the farm and had it 95% ready to go. When my ticker started failing last summer I made a "U" turn (not the first one in my life

) and I decided that I was not going to spend what time I have left working. I am generally recovered now and I am going to sell a few heavy machines that are specifically shoe machines but keep all of my hand tools and the machines that are good for general leather and harness work and move those to the basement in a smaller room right next to the woodshop. I could crowd them into one corner of the woodshop but that sewing equipment doesn't like sawdust.
My leather work tends to be a lot like my woodworking. Plans, patterns or a lot of oddball dimensions just are not part of it.

If I want to make something I just picture it in my head and make it. It does help if I have a picture.
One of my BIL's makes a lot of really nice furniture, some of which he sells but I'm not sure he could make a toothpick without having a full set of plans to study every few minutes.
Different strokes...
I have not moved my pics to this laptop yet so I found a few on-line.
A Singer patcher looks like this.
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A sole stitcher looks like this.
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A McKay type stitcher looks like this.
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A flat bed sewing machine looks like a flat bed sewing machine.
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