How do I add mods to Minecraft PS4 without a computer?

Unless you jailbreak the ps4 and ask someone to make a mod suitable for minecraft on ps4 than no. Sorry because for one thing there is no mod capable on a PS4 and 2 you need to jailbreak a PS4 first. Sorry, no mods for ps4 unless you know how to program in java and know how to jailbreak a PS4.

if you have Minecraft on a mobile device you can get the mod you want on the mobile device and on invite your ps4 profile to it and that should work if it doesn't check this video.