(1) If any one watches TV wudhu will be broken. We have to do once again wudhu for namaz, if we watch TV.
(2) As per Ulama, shall we attend birthday parties and eat food there or cakes.
بسم الله الرحمن الرحيم
(1) No, wudhu does not break by watching TV. However, if one discharges madhi or mani in case he watches nude pictures or nasty programme then wudhu shall break in case of madhi and ghusl shall be wajib in case of mani.
(2) It is not Islamic method to celebrate birthday and throw party rather it is the invention of other nations hence Muslim should avoid it. Also should not attend such programme and should not eat food or cake etc from there.
Allah knows Best!
Darul Uloom Deoband