Hi! This is exactly how I started out last year!!!
The tips I have are:
* To learn where the notes are on the keyboard, and where they are situated on the musical stave, in both treble and bass.
* Practise playing by ear the songs you know, and use sheet music to guide you...this will help get you familiar with how rhythms and notes look and feel to play.
* Get yourself a theory book. Some find this boring - personally I'm addicted to theory - I love it!! This will help you to understand music and will prove helpful when you come to learnt to read music.
* Practise scales, arpeggios and broken chords (you can buy books specifically, or look them up on the internet). Don't underestimate the value of this. They will help with your improvisational skills, and will also help you play more fluently, and will expand your overall knowledge of the piano.
* And last but not least (in fact, probably most important!!) PRACTISE! Practise makes perfect, however long it may take!!!! I practise on my keyboard/piano practically 24/7, and I'm hoping it's paying off (well, I think it is, coz apparently I'm quite advanced bearing in mind I've only been playing for a few months!!!)
Good luck, if you need anymore help, I'd be more than happy to advise you