Using iCloud storage differently on iPhone and computer

I have an iPhone and an older MacBook Pro on my AppleID. I have a large number of photos in my Photos library on my computer that I do not want to store in my iCloud storage. Can I turn on iCloud storage for my iPhone photos only? (I realize that once I turn on iCloud backup for my phone, I will no longer sync my phone with my computer.) In other words, if I turn on iCloud storage/backup for my phone photos, will that in any way affect my computer Photos library? I want future photos I take on my phone to be stored/backed up in the cloud but I want to leave my current computer Photos library as is.