You are in a very rough patch, especially for a newbie. Going through the lower torments is a bit slow and can get a bit boring.
Basically, if you are stuck in T4, that’s okay. No worries. Here are a few steps and a bunch of bla bla bla to help you get out of the lower torment slump.
1: If you don’t have it, get the Cube. You will need that big time. Go to act 3 and look at the map, press m, and choose the top waypoint ‘The Ruins of Sescheron.’ It’s a bit of a pain to get to. Just clear each area and go to the next area. Rince and repeat and you will eventually find it. The best way to explain it, or even better look it up online. If you have that already, disregard the bla bla bla, I tend to get a bit long winded.
2: Do a ton of bounties, especially since you will need the materials later. While you are doing those, you will find a lot of legendaries as well as getting the bounty ones. Of course equip the best ones you have. Also, look at anythying you can craft. If you have the sage set, craft it. You will get double death’s breaths and you need those for later.
3: Once you have say 50+ bounty mats in all five acts, start doing rifts. Of course by now you should have found a bunch of legendaries from mobs and bounty caches. If you can, start collecting Wrath of the Wastes set pieces, even crappy ones, you just want that lovely 6pc bonus set. If you find the Lamentation belt, keep it, even a crappy on. If you find the sword Ambo’s Pride, keep it, even a crappy one. Use the cube (page one) to extract the power from the belt and the sword if you have it. Select each one and you have passive powers. WOOT! If you stumble upon a band of might (ring) keep it. You can either wear it or put in the cube. Same thing with ring of the zodiac. Keep an eye out for the 2 bulkathos swords (green items).
4: You will need a ton of greater rift keys anyway, so go crazy and do a bunch of rifts.
5: Once you have a lot of greater rift keys, say 50 or more, start doing greater rifts. At this point you should have 4-6 pieces of the Wastes set and maybe even the belt and sword in the cube. If not, then by the time you have a ton of rifts, you will.
6: Greater Rifts. Lots, and lots, and lots of them. At the end, you get loot, and a legendary gem. If you beat the greater rift timer, you can put levels in your legendary gem. Look out for Taeguk, Bane of the Trapped, and Bane of the Stricken. Get those 3 to level 25 to unlock their special power.
7: You should be able to start testing out the higher torments. You should be good to at least T13, maybe even up to T16. Then you start the endless game of finding upgrades. There are ancients and even primal ancients. Of course, later on, you will be into enchanting your items for more goodness.
Now, I suggested the Wastes set because it’s easy to use (spin around and kill stuff) and buff once you have all the pieces in place. Make sure you use the charge skill or whatever is your liking to make uses of the Ring of Might’s ability.
Icy Veins, Maxroll, and to a lesser extent Diablofans are good sights to get guides, build breakdowns, explain skills, what gems to use, etc.
Then you do it over and over again with either the same class or another. This game will keep you busy FOR A LONG TIME!
Enjoy.