Help improve team(basic sun team-UU)

[ThreePosssumsInaCoat]

Hello, I'm a new showdown player that's recently gotten into competitive Pokémon, I've been using a slightly modified version of the the sun template team found on the website, and have been struggling with battles for a while, and I cannot for the life of me figure out if it's a team problem or a skill issue if you have any tips on how to improve my team, that would be greatly appreciated.
Torkoal @ Heat Rock
Ability: Drought
Tera Type: Ghost
EVs: 248 HP / 16 Def / 240 SpD / 4 Spe
Bold Nature
- Stealth Rock
- Lava Plume
- Scorching Sands
- Rapid Spin

Lilligant-Hisui @ Life Orb
Ability: Chlorophyll
Tera Type: Fire
EVs: 252 Atk / 4 Def / 252 Spe
Adamant Nature
- Solar Blade
- Close Combat
- Triple Axel
- Synthesis

Slither Wing @ Choice Scarf
Ability: Protosynthesis
Tera Type: Fighting
EVs: 252 Atk / 4 Def / 252 Spe
Adamant Nature
- Close Combat
- Earthquake
- U-turn
- Flare Blitz

Sandy Shocks @ Assault Vest
Ability: Protosynthesis
Tera Type: Fairy
EVs: 48 HP / 208 SpA / 252 Spe
Timid Nature
- Volt Switch
- Earth Power
- Tera Blast
- Power Gem

Brute Bonnet @ Loaded Dice
Ability: Protosynthesis
Tera Type: Fairy
EVs: 252 Atk / 4 SpD / 252 Spe
- Trailblaze
- Seed Bomb
- Synthesis
- Sucker Punch

Cresselia @ Choice Scarf
Ability: Levitate
Tera Type: Ghost
EVs: 248 HP / 8 Def / 252 Spe
Timid Nature
IVs: 0 Atk
- Ice Beam
- Lunar Dance
- Moonlight
- Trick