Sadly, this is considered an cheat and code-injection inside Roblox witch breaks Roblox ToS. If you could print to the console, that would mean that you could also change your players walk-speed etc because everything you are doing is from the client-side.

This means if you achieved to print "hello", then you could also do client things like moving your character, flying, jumping really high etc., but you can't affect other players. If you tried to change the color of a part for example, only you would see it, not others.

Anyways everything that you are trying to do is an Exploit or cheat because it interacts with the Roblox Client in a malicious way, injecting and executing code. Also SynapseX is a paid cheat for Roblox that can perform more advanced things, still not Server-Side.

Only way you can interact with the Client without breaking ToS is changing the FPS cap, or adding shaders to the game, thats all.