I really agree with , PP saying dont just text asking if they are ok .
I found it insulting and insensitive when my DH died , of course I am not ok.
Depending on if your friend likes talking on video calls (whatsapp etc ) or more traditional calls. Drop them a text and say I am going to call you at X time so we can have a chat , that way they are expecting you and not some random cold caller but it also gives her the chance to say no thank you .
If you can not go and see her tell her you are going to send some food round , try not to take no for a answer , ask what she would like .
My DB sorted out a tesco order for me , easy to cook tasty things like ready meals , pizza , tins of Hinze big soup, jelly babies ( he knows I am a sucker for them ) a few cans of cider and one of things I would not of thought of very soft balm tissues so my nose did not get sore with all the crying and sniffing.
If you can go round , offer to look after DCs / walk Ddog / go for a walk together / go for coffee .
A shoulder to cry on is very nice but sometimes its the practical things she will need help with, do you know / find out her neighbours , ask them to put out and bring bins in , walk dog , pick up a few bits from the shop
Send her this link , it is not means tested and really helped me out for the 1st year
www.gov.uk/bereavement-support-payment
And if it is in place in her area
www.gov.uk/after-a-death/organisations-you-need-to-contact-and-tell-us-once
Also if you know what bank she is with send her their bereavement link, the RBS went above and beyond for me . here are a few links but all banks have them
www.rbs.co.uk/life-moments/bereavement/bereavement-guide.html
www.lloydsbank.com/help-guidance/life-events/bereavement/notification-form.html
bereavementservices.digidocs.natwest.com/Login?SelfService=true
www.santander.co.uk/personal/support/customer-support/bereavement
www.postoffice.co.uk/social-responsibility/help-with-bereavement