Can you use old lenses from a camera on a new one?

Presumably they are dsl s but I'm not that good at photography, but I'm pretty sure Since they couldn t be anything else since their worth

Yes and no.

Entry level digital S: R cameras use specific lenses, usually just the current ones.

Many camera s have changed lens mounts over time.

* Sony bought Minolta in 2006 and for a while used the Minolta A-mount. Now a decade later, they use a different mount called the Sony E-mount. Using those old lenses on new cameras can be problematic
* Canon changed their mount from FD and FL to the new EOS lens mount called EF for 35 mm and full frame cameras (which can be used on cropped sensor cameras) and EF-S mounts lenses which can only be used on cropped sensor cameras.
* Pentax finally moved from the old M42 screw mount lens to a K-mount bayonet lens, sadly long after they lost their huge market share.
* Nikon advanced camera bodies (usually those costing over $1,000 for the body only) can use All the Nikkor AF, AF-I, AF-S and AF-P lenses as auto focus lenses and can also use Nikkor manual focus AI lenses.
* Olympus can only use 4/3 or Micro-4/3 mount lenses. The older excellent glass made for there 35 mm OM series cameras are not useable on the new Olympus digital SLR and mirrorless cameras.

There are third party lenses which can be used on certain camera bodies, most notably Tokina, Sigma, Tamron and a myriad of lenses now coming out of Korea. These third party lenses are NOT available for all the different camera brands, so you will have to make sure that the lens(es) you wish to buy for your camera from one of those companies is made for your body.

Note: My newest Nikon camera, the D500 is capable of using my over 40 year old Nikkor, AI converted lenses, most notably a 105 mm f/2.5, 55 mm macro f/3.5 and 20 mm f/3.5 lenses. I'm able to use the electronic rangefinder in the camera s viewfinder and can set the camera to accept "non-cpu" lenses so I can use the camera s lightmeter

To know for sure which "old lenses" will work splendidly on your new camera, you will have to do your own research Probably.

It depends on the mount of the lens. With Pentax, any lens made by or for the Pentax will work with any Pentax dSLR. My wife is using those same 40-year-old Nikkor lenses on her D5100 without issue.

As has been mentioned, it depends on the mount. You need to know which mount your camera uses, and you need to know which mount the lenses have. Without that information, nobody can actually answer the question.

Probably.

It depends on the mount of the lens. With Pentax, any lens made by or for the Pentax will work with any Pentax dSLR.

My wife is using those same 40-year-old Nikkor lenses on her D5100 without issue.

As has been mentioned, it depends on the mount. You need to know which mount your camera uses, and you need to know which mount the lenses have. Without that information, nobody can actually answer the question.