Must I develop my bishop on next move? I got to this position, while playing this game: https://lichess.org/dT3d9Dp4

Here I feel the need to develop my bishop. I thought of Bf4 but I feared g5, after  which I will lose a tempo. Be3 always make me think of a pawn fork on d4 or e4. I feel Bd2 is too passive. What frustrates me most is that developing the bishop might not even be necessary at this position. How will I know what to do? Is developing the bishop necessary?

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1.e4 Nc6 2.d4 e6 3.Nf3 h6 4.Bd3 d5 5.O-O Nge7 6.Nc3 a6
You don't have to develop your Bishop on the next move. Bf4 does look ok, however. Re1 also looks good as it will support the e pawn.