Splitting always results in signal loss. So it’s only beneficial where signal is “too much” which is rarely the case.
So generally speaking you’ll want an amplified splitter and as @MotobikeMan has stated, buy 75ohm “terminators” for any unused.
I’ve used several. If you don’t do online ordering, Channel Master splitters are usually out there in stores somewhere, and they work fine.
My primary junction box splitter is an 8way amplified splitter. But I needed more ports at my study, so I added an amplified 4way there. Realize you don’t normally want to keep on splitting, because nothing is “perfect” and so there isn’t a perfect amplify-split -> amplify-split -> etc thing you can just keep on doing. But for my purposes, it worked out ok.