It's absolutely correct to begin a sentence with "to".

It's correct to begin a sentence with "to". For example, you can say:

To take advantage of all job opportunities, follow us on social media.

"To" is a preposition that typically has a noun (e.g., "to New York") or an infinitive (e.g., "to walk") as its object. When using it at the beginning of a sentence to create an infinitive phrase, be aware of:

1. Commas. As a general rule, use a comma after an introductory phrase starting with "to" (learn more about commas with "to").

   To promote a better environment and working conditions, we should work in harmony.

   To promote a better environment and working conditions we should work in harmony.

   The comma, however, can be omitted if the introductory phrase is clear and short (no more than four or five words).

   To succeed you must first learn to fail. (The comma after "succeed" is optional.)

2. Emphasis. You can introduce a sentence with "to" for emphasis. Be aware, nevertheless, that overusing this structure can be problematic from a style perspective.

   To learn to play the guitar, you need a good teacher. "(It shows emphasis)"

   You need a good teacher to learn to play the guitar. "(A more neutral version)"

3. Negative sentences. We don't use this construction to start a negative sentence. However, you can change a negative sentence into an affirmative one by using verbs such as "prevent", "avoid", "increase/reduce", "improve/worsen", etc. For example, instead of "not to annoy your parents", you can say "to avoid annoying your parents".
4. In order to. When using an introductory phrase to show purpose, you can usually replace "to" by "in order to". Keep in mind, however, that "in order to" is more formal as well as more common in writing.

   In order to prevent water pollution, avoid flushing unnecessary items down the toilet.

As mentioned above, "to" can have a noun, instead of an infinitive, as its object.

To my surprise he remembered my birthday.

At the beginning of a sentence, this structure is much less common and frequently more formal or literary.

To my incredible and resilient student, keep setting high personal and academic standards for yourself.

We follow the same comma rules in this case.