First of all, the correct preposition is "to" not "too". After "to look forward to", you need the progressive form. So it would be: I look forward to seeing you. By the way, if you can use grammarly.com to improve your writing. It underlines words where the spelling or punctuation is wrong and also helps with grammar and the correct use of prepositions.

Hi Ramin, In general, we use to with verbs in the infinitive form (base form). For example, "to go", "to run", to "examine" are all correct. There are, however, some exceptions. 1) I am looking forward to seeing you. 2) I am used to working long hours. 3) I prefer dancing to walking. These are some exceptions that are commonly encountered when using the word "to". Hope this helps. Cheers, Lance

it depends on the context...'I am looking forward to seeing you'...

Why not 'see you' ?

I look forward to seeing you