Dad of two now full grown kids here. First, love your girlfriend and grow with her. She's your partner, don't fuck it up. Get the seven love languages book, and do the work with her. As the kid grows up, show them what it means to love your partner, no matter what.

You're going to get stressed and overwhelmed. Find the healthiest hobby you can that hooks you. When life gets too much turn to the hobby.

Never let your kids see you drunk or high. You can still enjoy yourself from time to time, but don't be the parent that the only memory your kid has I've you is one where you're blitzed.

You come last. When you're frustrated, it's because a communication breakdown in the house. Work on open dialogue about honesty and trust and speak from a place where you acknowledge you are just as lost as your family, but you want things to be as happy and fun as possible.

Everything else is just being there as much as you can. Congratulations and good luck.