Joining a gym tomorrow. Any advice?

So surprisingly a random person I met on a stupid android game was one to make me feel better about myself and I realized I'm not ugly, but I'm still fat!

Anyway starting tomorrow I'm giving up fast food, high calorie drinks and joining a gym. Any advice is appreciated. I'm 5'8" I weight 295(Give or take a few) and my goal is too weight 200.

Yes I know this is my 800th question on this type of subject, but sorry. It's odd how this girl convinced be but she did. So yeah time to get some good stuff going in my life.
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Oh I get a consultation with a personal trainer once for free too.
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Oh I'll also be cutting out junk food. There isn't much left in my house thankfully.
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If anyone cares about how I'm doing on my weight lost I'll update this ever week(every Thursday) if you want me to.
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I was wrong on my weight I'm actually 283.
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Well I haven't gone to the gym at all because I'm retarded, but my weight has stayed even. So I guess that's a good sign that I'm improving. I'm going at 10 today and I got 4-14 day passes so hopefully I can find some people to go with me.
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Well now I'm almost 280. That's 3lbs from just changing what I drink. My fitness consultation is Tuesday so I'll finally start going to the gym.
Joining a gym tomorrow. Any advice?
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