>>1529166>>1529152you have a "coaster brake". if you can shift gears in the hub, then you have an IGH with a coaster brake.
it's not super hard to add lever-actuated brakes. however, different frames/forks are set up for different types.
you get 70% of your braking power from the front brake, so opting to just get that one is an acceptable and popular option (especially since you have a rear coaster anyway.)
also, aside from the brakes and levers, you need cables and housing to connect the two. these are sold as kits with all the tiny end-pieces, so get that.
>caliper brakes they bolt onto holes through the fork "crown" and a "brake bridge" across the seat stays over the rear wheel (there may be a reflector there, too. you can put the reflector through the brake bolt, too, if you want to keep it.) if you see holes there, buy a set of calipers and levers *that say they work with caliper brakes*.
>cantilever/V-brakesthese bolt onto "bosses" on either side of the wheel on the fork and frame. the levers that pull them are different than caliper brake levers, so pick the appropriate lever
>discI'm assuming you would know if you had a disc frame, but it has reinforcements near the wheel mounts and there's another bit down there with holes through it where the brake mounts so it can clamp the wheel-mounted braking surface ("rotors"). there are versions that use hydraulic cables, or regular braided metal cables. again, these use their own kind of lever.
if your frame doesn't have any mounting points, drilling the metal on your fork crown and brake bridge out isn't especially hard to do but you need to be sure you do it at the right measurement for the caliper to hang the appropriate height and also straight through: perpendicular to the fork/parallel with the wheel.