There are a few things to consider if you are looking to volunteer with a business. The key thing is that you can’t take on a role, or take over work, that should be done by the paid staff, and your volunteering shouldn't support the business itself.
For example, you could provide additional support to residents at a private care home (which is a business), such as spending time with them to enrich their lives and provide activities, personal support and companionship. But, you wouldn't be able to take on care responsibilities, which should be provided by the company/staff running the home.
You can find general ideas for the Volunteering section here and DofE’s ideas for volunteering from home or remotely here.
There have been some temporary programme changes during the pandemic, so you can currently volunteer to support a family member. Find out more about DofE’s temporary programme changes here.