It is essential to deepen your understanding of strategy and to become familiar with the characteristics of the Premier League
「戦術理解を深めプレミアリーグの特性にも慣れる必要がある。」は英語で「It is essential to deepen your understanding of strategy and to become familiar with the characteristics of the Premier League」という表現が良いと思います。
戦術理解を深めーDeepen (your) understanding of tactics/To cultivate a better understanding of strategy
プレミアリーグの特性にも慣れるーTo grow accustomed to/To get used to/To become familiar with The characteristics of the Premier League
He needs to deepen his tactical understanding and get used to the style of the Premier League.
- *He needs to deepen his tactical understanding and get used to the style of the Premier League.*
- *He has to improve his tactical awareness and adapt to the demands of the Premier League.*
「戦術理解を深める」は英語で *deepen tactical understanding* や *improve tactical awareness* と表現されます。
「プレミアリーグの特性に慣れる」は *get used to the style of the Premier League* や *adapt to the pace and intensity of the Premier League* のように表現できます。
アメリカ合衆国 
