Bale's fitness has been a major concern for Wales, with him yet to play a full match for Los Angeles FC due to injury issues.
The forward helped his side win the Major League Soccer Cup, but he heads into the World Cup having played just 28 minutes of competitive football since September.
Asked where he is in terms of his recovery to full fitness, Bale told reporters on Sunday, "I am right where I want to be. I am here, right before the first game and ready to go.
"We have all been training hard in the last week and adapting to the heat and time zones and we have no excuses now.
"We put the hard work in and it's game time tomorrow and that's hopefully where we can step up and deliver what needs to be delivered."
Wales will be playing at a World Cup for the first time in 64 years, building on their achievement of reaching the Euro 2016 semi-finals and the Euro 2020 last 16.
"As a kid, you dream of seeing Wales at the World Cup but to actually be in the team that achieves it is an incredible feeling," said Bale, Wales' all-time top scorer with 40 goals in 108 games.
While Bale will lead Wales at the Ahmad Bin Ali Stadium on Monday evening, the team will miss Allen due to a hamstring injury he picked in mid-September while playing for Swansea City.
"We said from the start, we're going to give every chance that he can to play that first game, but he's not going to make it," coach Rob Page said.
"We could have pushed him but if he breaks down then he's definitely out of the tournament. Risk over reward. We're not going to push him to the point of losing him."
With England expected to advance as winners of Group B, the US, Wales and Iran could face a tight battle for second place to qualify for the knockouts.
"You look at England and USA, naturally people will talk about them as the top two and then us and Iran. But we know on our day, we have proven in the Nations League... that we can more than compete as well," Page said.
"We are new to the tournament and there might be a few surprises on the way. There's no pressure on us, we are going to enjoy it. But we are going to compete... We have earned the right to be here and I want to show the world how good we are."
