Deleting back up

To whom it may concern,

Hello, I was wondering if I delete a back up will it delete everything off my phone currently. I wanted to free up some storage on my phone and I deleted a lot of

messages and photos which were taking up majority of my iCloud storage. I already had a previous back up on my phone and wanted to delete the old back up and then re-back up what is on my phone now but I’m afraid to delete the old back up because I don’t want it to delete everything off my phone.