Give it time to mix - there’s a myriad of things going on with fill water. When I fill up my hot tub it looks like that for a couple hours until all my adjustments take effect & it filters a bit.
You can always add chlorine any time of day or night- if you need it add it!
As for a robotic cleaner- they’re nice to have but are also expensive. That’s a personal choice not a must have thing so long as you have a way to vacuum your pool.
There are many threads here on the subject
The selection, operation and repair of pool cleaners.
www.troublefreepool.com