I am wondering if the hooks in front will be uncomfortable, How does it feel?

This is the most comfortable bra you will ever find. You will never know the hooks are in front. A bonus if your shirt is low cut you can undo the top 2 hooks and it still fits perfectly. I wear a 38DD and it fits perfectly on me sz 38

Is this one or two bras?

It depends on the options you pick. If you pick one then it's 1 bra, two it's 2 bras and three it's 3 bras. Then you pick the color you want if you pick one and if you pick two or 3 then there's sets of color combinations. I mean it's all self explanatory right under the photos where the options are. I don't think they could have made it any clearer.

How comfortable is the bra and does the front closer prevent a uni boob? Does this style compress your breasts?

I am wearing these post lunpectomy as my daily bra because they are soft and comfortable. Not compression bras for post op. For smaller breasts, B and C maybe. No Uni boob. Not a supportive jogging bra.

Does this bra have adjustable straps

No. It does not have adjustable straps. You really don't need to adjust them. You are held in firm if you chose the right measurement. Don't guess. Measure yourself. I love mine. Very comfy for around the house. I broke my wrist so I could not hook a normal bra. I could hook these that hooked in front.