Will my game fit on the available HDD space?

I have FFX/X-2 remastered and am trying to install it on PS4. Despite uninstalling some of the TV addons like Netflix & Hulu, there isn't enough space for installation.

How do I estimate the amount of disk space necessary and how much is needed to uninstall?

BlueBarren is correct. i am fairly certain that every PS4 game has the Required HDD space on the back of the cover, for instance Final Fantasy XII: The Zodiac Age says it needs about around 40-something GB which is way to much for a save file, which it too is also listed in the back.

i have noticed all physical PS4 games i have brought are also available digitally as such disk space should also be documented in the Playstation Store, both on the PS4 and the Browser Version. However since this is a digital version and thus doesn't have a disk to play off from the size would be greater, but if you go by this size as an estimate you will be certain you have enough space if you play a physical version

for Final Fantasy X/X-2 on PS4 it's digital version required 32.1 GB for the game and 11 MB for saves minimum. the latter will always be the same regardless of what version you play

it is also quite possible that the same can be done for XBOne games however i don't have an XBOne to double check the store, however i do recall on the XB360 the store on it would list Disk Sizes for games so assuming the same for the XBOne you can too use this as an estimate for a physical games

There are sites that have a list of almost all game titles with their installed sizes, which makes it far easier to figure out what to uninstall to fit in a new game on an almost-full disk.

PS4: https://www.finder.com/complete-list-playstation-4-install-sizes-460-titles

XBox One: https://www.finder.com/xbox-one-install-sizes