I just started yesterday and my equipment sucks even though I have great ships
Try to Refit re0eats
You should have 4 battleships and 2 destroyers to get through battlelines easily, try to get to the battlelines that gives you the t3 main battery blueprint and grind it until you have 4 star main battery for your battleships. Always play pvp to get promotion gems and get 5 star battleships. Later prioritize 5 star main battery first since it can give you 70% extra damage, 40% critical damage and 15% critical chance.
I use 4 battleships,1 destroyer,1 cruiser with Torpedoes(Takao) and Amagi
You can use cruiser for battlelines with few battleships, otherwise use destroyers instead. Also upgrade all your battleships to unique first, then destroyers. South Carolina, West Virginia, Gneisenau and Warspite are the best 4 star bbs in my opinion if you don't have all 5 star bbs
I have 5 star Missouri,Iowa,Bismarck,Yamato,blah blah blah...
Oh, then you pretty much have the strongest ships in the game, just upgrade all of them to unique and get 5 star main battery
North Carolina is best 4 * battleship, but Gneisenau and Warspite are some of the weakest because of their low number and slow secondary weapons.https://docs.google.com/spreadsheets/d/14nh7aj1pFAzOxElHrd6wtrdmHv-uhbKXjPCUBhYu1zY/edit?usp=sharing
Senna I might run out of ressources