Eh, HoloGra is basically a weekly short video series with a bunch of inside jokes about the Hololive idol group. It's episodic and you won't understand any of the context without keeping up with the community. A lot of it is nonsensical and the plot boils down to whatever random stuff the talents and staff want to put out.
It's very balls to the wall wacky with some slapstick comedy. I enjoy it from time to time, but I would never recommend it to a casual anime fan. It's also probably the worst way to introduce anyone into Hololive or vtuber culture in general.
If you think the character designs look cool but you don't like streamers, and want an actual story. Maybe wait for Hololive Alternative? (If that ever comes out).
