Some questions about preposition. Please help me!!!

Hi!

Could you please, help me with the following?

The correct is:

a) On the right moment or at the right moment?;

b) bitting or biting (from the verb to bite)? ;

c) Some day or someday ?;

d) explained them or explained to them?;

e) In the end of the day or at the end of the day?;

f) In the way or on the way I saw nice trees ?;

g) uncontrollable or uncontrolable? (does this second option also exist ?);

h) "We went to explore..." or (just) "we explored..."

Thanks in advance,

Beatrice