きょうのてんき！ヽ(＾▽＾)ノ

今はてんきをはれです！＾＾　私はとてもはれすきです！^^

はれ　is a noun, (meaning fine weather), so it can't be preceded by を. You can only have を - verb.

As far as I know, the way to say it is a fine day is きょうははれです。As はれ means 'fine weather', you don't need to say てんきがはれ　as that is equivalent in English to saying ’today's weather is fine weather'.

If the second sentence is intended to mean 'I like fine weather', then try 私はいいてんきがすきです。At the moment, your sentence lacks a particle to mark the object.  The thing you like has to take ’が’。

Of course I am not a  native speaker just a student of Japanese just like you - I am sure a native speaker can give you better advice, but this might help in the meantime.

きょうのてんき！ヽ(＾▽＾)ノ

今はてんきをはれです！＾＾　

→今日（きょう）のてんきは、はれです！

私はとてもはれすきです！^^

→私は、はれがとてもすきです！

-------------------------------------------

今日（きょう）・・・today

今（いま）・・・now

-------------------------------------------