如何将Android画廊中的图片附加到我的笔记应用程序中？

I'm developing a simple note app, some kind of diary but I need a function where I click on the "attach" button so I could attach files from internal and external memory from the phone, the files would be pictures and maybe, if possible, video and wav files, all of them together with the text file on the note app, and I would need to save all this in a database, so I would like to know if that is possible and how do I do it , I read about sharing files from apps to apps on android developer site but I got confused, so I would like someone to help if possible, btw sorry for my bad English I'm not a native English speaker and it's my first time asking here, so I would be glad of somebody could help with this. I'm developing a simple note app, some kind of