The rough but easy way is to say ö is "er" Many English people who can't speak any Geran say "Ger-te" for the writer Göthe.
But we should make more of an effort than that. Try this exercise for the word König (King). using English pronounciation first say "Kernig" then say "Kornig"; repeat: "Kernig Kornig" as you carry on repeating try to merge the two vowel sounds as you merge to one sound, and carry on repeatig the word. Hopefully it is close to the word "König".
You can do this with schorn-schern to get schön a bit trickier is grerße-grorße to get Größe. Try practicing on other words as well.
First up, an e after the vowel is the same as an umlaut so use that when you can't type an umlaut, example oe=ö. The umlaut form is just aesthetically nicer so they are used when available.
Now to answer your question: schon means already. schön means beatuful, handsome, very nice, great.
schon is an adverb and never has an ending schön is an adjective. When it comes before a noun it needs an ending eg das schöne Mädchen.
You have written schöner which could either be "more beautiful" or it could be "beautiful" with "-re" as an adjective ending: ein schöner Mann
There are six conjugations of the verb 'sein' ('to be' in the present tense). Two of which are 'bin' and 'bist'. You use 'bin' together with the pronoun 'ich' when you wish to say 'I am ...'; 'ich bin ...'. You use 'bist' together with the second-person singular and informal pronoun 'du' when you wish to say 'you are ...'; 'du bist ...' to a friend, for example.