ok so,first....i would say"he drinks and eats to much' or he drinks and eat to much"without the "s'

secondly i would say"when i first tried it" or when i tried it first/when i first did it or when i did it first

third...what favors him last or what last favors him

4/ i dont even know where to start from or i dont even know where to start

thanks so much i really appreciate your help
"He drinks and eats too much." (He eats, he drinks, don't forget it's "too")

"When I first tried it..." (During my first time trying it)

"When I tried it first..." (When I tried -it- before I tried some other things)

"I don't even know where to start." ("from" would be redundant)

Sorry, I don't know the "favours" one -- I can't get your meaning.
thanks.i have another question is it right to say"it was nice going there and seeing the sky" or it was nice to go there and see the sky

for me both are correct>>>>am i right ??