Rayansaaddevgamesoffical

There is no real way to just make it smooth, it's up to the animator to make it smooth, but you can play around with the key frame transitions, 

When you have a keyframe on your timeline, then select transitions, rightclick it or go to your current object tab and scroll down till you see a "keyframe" section, you can choose between the different transitions, they all change the way something moves/rotades/scales, and with this you can basically make an animation smooth, but it takes practice!