Must the tabernacle be placed at the center of the Church? How do i genuflect?
The Canon law does not say “Center” but a conspicuous place in the Church is okay. The Code of Canon Law puts it this way:
The tabernacle in which the most holy Eucharist is reserved is to be situated in some part of the church or oratory that is distinguished, conspicuous, beautifully decorated, and suitable for prayer (CIC 938).
The General Instruction of the Roman Missal says this about genuflecting:
If . . . the tabernacle with the most Blessed Sacrament is present in the sanctuary, the priest, the deacon, and the other ministers genuflect when they approach the altar and when they depart from it, but not during the celebration of Mass itself. Otherwise all who pass before the most Blessed Sacrament genuflect, unless they are moving in procession (GIRM 74).