There is an internship in the third semester so I'd really love to learn about xx.
There is an internship in the third term which would be a great opportunity to learn lots about xx.
どちらも「３学期にインターンシップがあるので、XXをしっかり学びたいです。」という言い方です。何のインターンシップなのかわからないので、XXのところに学ぶ内容を入れてみてください。
1) There is an internship in the third semester so I'd really love to learn about xx.
2) There is an internship in the third term which would be a great opportunity to learn lots about xx.
「３学期」は third semester や third term と言えます。
「しっかり学ぶ」は really learn about ... や learn lots about ... と言えます。
ご参考になれば幸いです！
日本 
