My Guitar teacher wants me to start writing a song and i have no idea about songwriting

can anyone give me some tips

Well, first off, how do you want the song to sound? Fast? Slow? Upbeat? Sad? Deep? Higher pitched? Do you want to use a lot of chords? Do you want to use single-note melodies?

We can't help you until you help us.
I think the person that should be helping you is your guitar teacher... duh?

If you're unsure ask him, and if he doesn't want you to have any help then I would I follow his advice and not recieve help.

This might not make alot of sense but personally, when I try and write a song, I can't (Or at least not a good one). But when I just play and something sounds cool, and I build on that, I usually get some great stuff.

Good luck.
Find a chord progression. Play it. Find a similar, fitting, shorter chord progression. Find a bridge. Stick them together. Write lyrics. Sing and play.
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