What to look for buying a piano or keyboard
If you are just starting; anything will do! There are a lot of unused pianos and keyboards in this world, so see if someone will lend you something that you can play "Raindrops" on and get used to playing your fingers 1, 3 and 5 learning chords. You can also find them at second sales places, like "market place" on facebook.
Of course it is much more of a pleasure and it will help you truly find your inner musician if you have an instrument you love.
There usually are two considerations: 1. Budget and 2. Whether to go for an acoustic, wooden piano, or a digital keyboard.
If you have the space an upright or grand piano will give you a lifetime of pleasure. It will nurture a better playing technique and they usually have more of a story / personality. I believe wooden pianos are easier to love, and that that love is something that will make your music sound better. Their prices range from "free" for a piano that is just looking for a good home, after its owners can't accommodate it any more, to several hundred thousand for the customised Fazioli I have on my wish list... With a second hand piano, make sure you love the sound. I strongly recommend investing $100 or so in getting a piano tuner to assess it for you. We live in an era where a generation of pianos is retiring. They can be complete rubbish, but there are also many fine instruments out there, that may go for a very reasonable price. Remember, with acoustic pianos there are ongoing costs of getting it tuned regularly.
Digital pianos are also brilliant. They take less space, can be portable, don't need to be tuned, can have their volume turned down or be played through headphones and can be plugged into computers. They don't go out of tune, and with good treatment can also last a lifetime. You want to look for something that has at least 81 keys (7 octaves) and that has a sustain pedal. You can support your local music shop and get advice and warranty. Or you can spend a bit of time to find what suits you second hand.
I believe there is nothing nicer than nurturing your inner musician. My pianos are way nicer than the car I drive. Learning the piano is a journey that will bring you endless joy and stimulation and companionship. I always encourage everyone to get the nicest piano they can afford. You deserve it; you are investing in yourself!