Hello MzVicki,
Welcome to the community.
This is a common question in plumbing isles.
It’s very simple to figure out what kind of bathroom faucet you need. The easy rule of thumb is if you have a one piece deck plate than you have a 4” on center if they are 3 separate pieces than it is an 8” on center. The only one that would differ from this rule would be what is called a mini-widespread faucet and they are installed on a 4” on center just like the one piece deck plate. There is also one that come in a single hole configuration but this is not very common in the bathroom.
Here is a picture on how you can measure the one you have to confirm what size replacement faucet you need.
**If the faucet is installed and it would be easier to measure it from the top you can measure from the middle of one handle to the middle of the other. If they are lever handles then you will measure the distance between the 2 screws in the handles.**
Once you know what size you need you can visit your local Home Depot and choose from the wall of bathroom faucets in the plumbing department or go onto homedepot.com and choose from the hundreds of faucets that are offered there.
Thanks again for joining the community.
Let me know if you have any other questions. I would love to help.
