The spent primer in a center fire case is removable from the brass case after being shot which allows a new primer to be installed, powder to be replenished, and a new bullet seated all with a practical amount of effort. After this process, the cartridge is ready to be fired again. This process is referred to as reloading.
Rim fire cases can be reloaded but not practically. As far as I know, there is no tool on the market at this writing to remove the dent from the rim caused by the firing pin. There are some tools available to assist in reintroducing primer compound into the rim. Then powder must be replenished and a new bullet seated in the case.
There is a kit designed to help you reload rimfire cases. It is called the Sharp Shooter. I have never used this one or any other like it. At this point it seems like a lot of work to me when you can buy a new round for 4 cents each. But if you are looking for a new hobby or are the type of person who enjoys the challenge of something different this hobby may be just right for you. Check it out here.
Mixing and reloading the primer compound is dangerous, impact is what makes this stuff explode. When mixing the components of the compound extreme care must be taken. Replacing removable center fire primers is much safer
Rim fire cases are much thinner and flimsier than center fire. Only a couple of reloads will be possible before they split and are unusable.
If your desire is to reload for improved accuracy, a more realistic solution is to sort ammo for important variables like rim thickness. There are tools and kits available to make this go faster. Here is the one I recommend on Amazon.
This tool attaches to your calipers and allows quick sorting of ammo by rim thickness which is the most important variable for accuracy. Serious competition shooters use this technique with even premium ammo in order shoot those tiny little groups with benchrest rifles.
I was able to shrink groups from a Ruger 10/22 I own, down from around three quarters of an inch to three eighths of an inch using the technique. This was from a batch of bulk white box Winchester.
Sorting for accuracy is something that will improve your rifle's performance but it takes a person with a lot of patience and desire to do it consistently.