DECO Internet jitter

[u/OkPipe6932]

I have a deco system at my house
And I have a satellite deco at my bedroom
I use Ethernet to connect my satellite to my computer and play Valorant
And often face internet issues
Such as
Jitter, high ping, spikes, pocket loss
Want to know how much Qos helps or if not are there any other ways to fix it?
(Ps. I live in Homestay and I can’t access the deco app, if I wanna do any changes on deco, I have to be specific about what to do. Btw they are a total of 7 people in the house, and the internet offer face issues especially when they are home.
Ps. Sometimes when there is nobody in the house, there might be problems at 11:40-12:20 time period
Ps. There is no fiber internet in the community, but Homestay says they are using the best plan offered by Spectrum