A speech contains too many words is called -

• A speech of too many words is called a verbose speech.

• Verbose:
English Meaning: Using or expressed in more words than are needed.
Bangla Meaning: বাগাড়ম্বরপূর্ণ; শব্দাড়ম্বরপূর্ণ: a verbose speech/speaker/style.

So, A verbose speech means 'containing more words than necessary'.
- The speech that contains more words is called a verbose speech.

Source: Oxford and Merriam-Webster Dictionary