Yes you can use Amazon fresh without prime.
To use Amazon Fresh without Amazon Prime you just need to sign up for an Amazon Fresh Account separate from the Amazon Prime account.
There's no need to have both an Amazon Fresh and Amazon Prime membership but having both Amazon Fresh and Amazon Prime is worth it.
Amazon Fresh membership costs $14.99 per month on top of the Amazon Prime membership.
I have both Amazon Fresh and Amazon Prime and they are both worth it to me.
Amazon Prime and Amazon Fresh are worth every penny because they save me a lot of money.