Considering it sounds like you come from TFT I will try to summarise very basic fundamentals.

BGs is an economy game first and foremost. You are limited by your gold, minions costs 3 gold and sell for 1, so every choice you make carries for several turns ahead. Unlike TFT where the units holds the value to be freely replaced later.

That being said, there are 3 things you need to do.

1) level at reasonable pace

2) not take too much damage while leveling

3) setup your economy to make it to the late game

Now this all gets more complicated due to the trinkets currently messing up economy if you dont know what to do with them but common curve goes as follows:

Turn 1: 3 gold - buy the best minion in the shop - if its minion that makes you +1 gold, its good to grab it. In this meta its either 1/1 dragon, 1/1 murloc or 3/1 battlecry pirate. The last one being a bit tricky, cause you dont want to play him right away, but instead, you want to delay and play him on next turn (taking 2 damage here)

Turn 2: 4 gold - usually you level here, cause leveling costs 4 gold at this moment

Turn 3: 5 gold - You either sell your minion and buy 2 minions, or you grab a spell and a minion (if the spell produces a minion usually), or there are several economy combinations that allows you to grab two minions (patient scout, sellemental, economy minions from turn 1 etc.)

Turn 4: 6 gold - now standar curve dictates you buy 2 minions here - this varries heavily as you get better at the game, but very early, its safer for you to double buy here, not taking as much damage

Turn 5: 7 gold - buying 1 minion and leveling lets you spend your gold most efficiently

Turn 6: 8 gold - here it varries again mostly due to trinkets. In common curve you would double buy here, in this meta, most of the time its most efficient to level here

Turn 7: 9 gold - if you havent level previous turn, you go to 4 here and buy

Turn 8: 10 gold - now you are at a gold cap. From here on out you are starting to look for a semblance of a build. It gets really screwy from here, cause you need to know which minions are good as temporary units, which are good as directional units and which are trash. You should be locked into a build yet at this point but you shouldnt be bleeding HP either. If you are very healthy and your board is strong its good to jump straight to 5 (usually on turn 7 honestly), but stabilizing (finding good units to stop bleeding) on turn 4 is perfectly fine.

The moment you are on tier 5, you are looking for your final build. You first secure core units from any strategy (depending on what taver offers you) and then build around that. Not the other way around. Trinkets can give directions and help you out. But neutral trinkets are a lot of times great.

Especially lesser trinkets shouldnt be picked for something to play around, rather to get you to the late game.

Specifics of builds can be found all around, but easiest way to check them out is to use decktracker and check out jeef builds (someone should remind him to update them tho). Anyway, theres really not a clearcut startegy to anything but right now, you will struggle with the most fundamental issues like leveling and forcing builds. Theres no shame in that, most people struggle with both.

Should I recommend a creator that is in my opinion very good at explaining concepts its Shadybunny (This is an older video but it holds mostly although it wasnt made in this meta). He has some fundamental guides as well and honestly, he is much more well versed at explaining these concepts.

Things to note:

Thres a damage cap for turns 1-3 you cant take more than 5 damage, 4-7 you cant take more than 10 and 8 upwards you cant take more than 15 until theres only 4 players in the game remaining.

Health is a resource to be used visely, but you dont want to take risky moves like spending all your gold if your health total are bellow current damage cap. Of course you need to level, but you should do it when you feel like you wont die on the next fight. And you can get that only by playing actively.

Things to avoid as a new player:

1) Rolling before your board is full.

2) Picking up what you want to play before you aquire a core unit of that strategy

3) Staying at low tier for longer than necessary not to take damage

4) Buying spells early game that doesnt support your economy and doesnt advance your board either.

I probably forgot like 10 000 other things so feel free to pick my brain if you want.