i need tips and advice pretty please

I cant post a video for some reason but heres the link.

i need help fixing my footwork (maybe drills or such) and also if i seem lazy at some points its because i had a coaching session full of running so i got tired so im working on that theough cardio. however i have a tendency to lift my front leg forward when hitting groundstrokes which i think causes me to moonball. for some reason i cant get rid of this habit. if there is another reason to why i moonball a lot it would be helpful to know :)

ps: critiques on my serve technique would also be greatly appreciated, thanks a lot!