Next best move and mistakes thus far

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rashidarvioreyhan

It's white's turn to move, what is the best move (along with why) and what were the mistakes thus far:

 

That's the board, the game up till this point is listed afterwards:


 

Thanks for the comments, looking forward to hearing your suggestions.

Tom_van_Diepen

I like the look of Be3, followed by a3, threatening the (pinned) knight on c5.

rashidarvioreyhan

What about mistakes?  Do you see any mistakes thus far?

Mainline_Novelty