I have a Ainol Novo 7 Flame, i have been using it for 3 years, and today it just got stuck in the booting phase, i didn't install any app or changed any settings, i dont even know why this is happening, google suggested that i do a reset to fix this problem, but does this reset actually removes my data?? and is the reset the only solution i have?
I will make some assumptions here since you don't give enough details.
I think that by stuck on boot you mean you soft bricked your phone but yes it weird if you don't mess around with root or other things and that just mean that if an factory reset + wipe cache don't work( and often won't ) you need to reflash the stock ROM again.
By "hard reset" you mean Factory Reset when you do that your phone go back to the factory state and all /data is deleted that mean all photos messages documents everything.
This process is often required but if your phone can still turn on recovery/download mode using an special sequence of buttons(google for your device ) you can still do an backup by using ADB it's quite simple and i recommend you to go xda-developer forum and search for an tutorial they have plenty tutorials for flashing roms rooting and much more stepts by step that anyone can execute without lots of knowledge just search for "backup via ADB"