grammar - Capitalization rules when the sentence begins with a number

The context is about work progress. Planned work is 100%. Someone implemented only 45% of the work.

45% of the work was implemented.

The sentence begins with the number. Please write whether we capitalize the first letter after the number? Is it normal in English if a sentence begins with a number?

Answer

No, you do not capitalize the first letter after the beginning of the sentence...

BUT

You should not start a sentence with a numeral.

You should either rewrite the sentence or write the number out fully:

Forty-five percent of the work was implemented.