Not sure what you mean by "
cumulative counts"...
I'd suggest to use
WITH clause[
^]:
WITH CTE(Cust_Name, og_date, cul_cnt) AS
(
SELECT Name, Del_dt, COUNT(*)
FROM YourTable
WHERE Del_dt BETWEEN '2022-04-07' AND '2022-04-10'
GROUP BY Name, Del_dt
)
SELECT *
FROM CTE