Does it matter what team I watch during pregame warmup or does certain official have certain team they are responsible for before tipoff?

Under NFHS rules:
2-man crew: R has the Visitors, U the home team
3-man crew: U1 has the Home team, U2 the Visitors, the R stands at the division line

thankyou, have another silly question do most officials leave there jacket in the locker room after halftime or is it better to wear it during haftime?

Jacket
 

Suggestion...Leave your jacket in the locker room at half time. It's best when final horn sounds to be able to meet with your partners near mid court and head directly to the locker room thus avoiding any unnecessary contact with coaches and players near the table.