Here are some of the reasons why each instrument is great to have
Guitar: it is accessible, fun and rewarding. Learning to play the guitar will develop your memory and coordination, as well as focus and social skills. Guitars are vital elements of bands and ensembles. For this reason, the guitar would suit you if you prefer spending your free time together with friends.
Piano: learning to play the piano improves coordination, hand independence, and muscle memory. It is also a very calming and relaxing musical instrument to learn. With a piano, all of the notes are right in a row, which will help you understand music theory behind it more easily.
Ukulele: it is a compact 4-string instrument. They’re portable; you can take it with you anywhere. If you’re looking for something similar to a guitar but a little simpler, this may be the perfect instrument for you. They’re easy to play and have a pleasant sound.