To To? Can you use “to” twice in a sentence in English grammar?

It is perfectly acceptable to use “to” twice in a row. This happens when you have a dependent preposition “to”(talk to) and an infinitive “to”( To eat)

Who do I talk to to get my money?

Where should I go to to buy a mask?

This type of construction is very common in spoken English. 

It is always possible to rephrase your sentence and for this reason, it is not very common in written English because it can appear awkward.

Many people would rephrase the sentences above in written English to something like:

Who do I talk to in order to get my money?

Who do I talk to so that I can get my money?

There are many ways you could rephrase the sentence but when you are speaking you often don’t have the time.

The reason “to” appears twice in a row is because the speaker is connecting two ideas and the first idea ends with a preposition(to) and the second idea(or clause of the sentence) begins with an infinitive(to get)

There is no problem grammatically speaking but it can make it more difficult to understand so for that reason many people would rephrase the sentence in writing.

The first verb always needs to be intransitive(it doesn’t take an object) or the sentence is a question so the preposition is placed at the end of the first clause. 

More examples 

Who do I have to respond to to get the answer I need?

How many newsletters do I need to subscribe to to get some valuable information? 

Many grammar checkers like Grammarly will highlight “to to” but don’t mind that, “to to” is correct.In saying that, “to to” can look strange in English writing so it is better to rephrase the sentence.