Latin is a little funky in that a language will definitely change over the course of hundreds of years.
In the Classical pronunciation (which is most common in the US), v is pronounced as a w.
In the Ecclesiastical pronunciation (which is most taught in Europe), v is pronounced as a v.
The letters "v", "u", and "w" all originate from the various sounds the letter has taken over time. In ancient times, there was just V and it had to make do with multiple sounds until the extra letters were added to make it a little easier.
"Tu vir est" is impossible because the conjugation of "sum/esse" in 2d person of singular is "es". You could write "Tu vir es".
"Tu es vir" and "Tu vir es" are both correct because word order in Latin is relatively fluid.
The most common sentence structure is Subject-Object-Verb (which you will often find referred to as "SOV" in these forums).
But the verb "sum/esse" is a copulative verb so it is also usual to put the verb in the middle of the sentence when it is involved.