Yes you can if you buy from shops that accept them. Once Get a bitcoin Visa or Mastercard to automaticaly convert bitcoin to fiat. This way you have 100% in BTC and convert in the last moment when you need it.
It depends on the grocery store or the market if they allow the bitcoin to become a payment tool for their business.
Some businesses are still not that knowledgeable about bitcoin due to its centralization. Also, it is volatile so maybe grocery stores are scared that they may lose the value of it when its price goes down.
But hoping that this adoption will become put in to place as this is what we need right now to prevent physical contact during payments. I heard about the bitcoin ATM where we can withdraw bitcoin instantly and hoping that more bitcoin ATMs should spread globally so that it is more convenient to us if we needed to do that.
In my country, there is still no grocery that are accepting bitcoin as payment but there are now small businesses like computer shop and coffee shops that are now starting to adopt cryptocurrencies. The progress in my country is too slow when it comes to mass adaption because of lack of financial literacy. Actually there are less than 10 bitcoin ATM in my country as of now and it seems that it will take more time before it doubles.
There are still a lot of people who do not have care about cryptocurrencies and I think it is the reason why merchants and other businesses are still having hard time to think whether they will start accepting bitcoin as payment or if they will stay using the old system.