Hi,
If you make only zero rated supplies then these are still considered taxable supplies and so there would be an obligation to register for VAT if your sales go over the £90K threshold.
However you can apply for an exemption from registration on the basis that your supplies are all zero rated.
Please see the guidance below, section 3.11:
Working out whether you need to register
If you do register for VAT then as a VAT registered entity you are entitled to recover VAT as input tax incurred in the course of your business.
Please see the guidance below:
Introduction to input tax
Thankyou.