Well, I'm not sure what your issues are in the guard. But I'll walk through some of the most common issues with the guard games that beginners have.
The first issue is that it is really easy to think that being in guard is like being on your back. At no point in guard should you be flat on your back. If your opponent is applying pressure you should roll back to your shoulderblades and the base of your neck. If they are backing off, then you should be sitting up to attack them. The guard game is really about making sure that you are using space effectively, making it and taking it away, especially taking it away.
The second issue is mobility in the hips. You have to move the hips to the sides and get them high so that you can attack armbars. You really want to be able to work your legs up into your opponent's armpits if you're attacking from the closed guard.
Other than that, I suggest working through individual techniques. If you need help with the details of techniques, I'm happy to work through those. But the guard theory stuff is really much higher level than you are ready for right now, having just started. It's all well and good to talk about, but it won't do you much good on the mat.
Sig by Toxic
Barnett - Toquinho -Werdum - "Nurmie"
Z. Gurgel - Morango - Rocha - Tiequan