Yes, you can gamble in moderation (entertainment), play games, smoke weed also in moderation and it's not sinful. Behavior that is sinful like watching porn cannot be fine in moderation.
There's no prohibition to any foods (anymore), so yes those things can be eaten in moderation, although healthier foods are often a better choice.
Scripture certainly gives Christians freedom in areas where God has not given an explicit command,
but the question isn't just, "Can it be done in moderation?"
The question is, "Can it be done in a way that honors Christ and doesn't gain mastery over me?"
For example, pornography is inherently sinful because it involves lust, so no amount of moderation changes that.
But with things like games, entertainment, food, or even gambling, I'd ask whether they're helping me exercise self-control or whether they're slowly taking control of me.
Paul said: "All things are lawful for me, but I will not be brought under the power of any." (1 Cor. 6:12)
That's the principle I keep coming back to.
As for marijuana, my concern wouldn't be moderation alone, but whether it impairs sobriety, judgment, or self-control, since believers are repeatedly called to be sober-minded and watchful. Every time I get my treatments, they give me something for the pain that is basically THC. I won't talk to anyone, I won't come on here, I won't do anything but sit here and pray till I fall asleep or the effect passes. I don't trust myself to act as I would with a clear mind.
So rather than saying, "It's fine in moderation," I'd probably say: "Can I do this with a clear conscience before the Lord, maintain self-control, and honestly say it is helping rather than hindering my walk with Christ?"
I think that's a more biblical test than simply asking whether something is explicitly forbidden.