The bets are determined by checking a wide variety of projections against my own knowledge of how players will be utilized given game context. The player prop lines were taken from this site.
When analyzing projections from fantasy sites, you'll often find that the projections are higher than betting lines, which will make you bet shit tons of overs. This is a common mistake. The projections are mean based, which tend to skew higher because the range of outcomes are not evenly distributed. (i.e., a running back on a good day could go for over 100 yards, but he would never go under 0... hopefully). If you find a mean projection lower than the Vegas line, the under is likely a good bet. To bet an over, the mean projection should be significantly higher. All bets below will follow that logic.
Sunday Morning Slate
Evan Engram u4.5 receptions +125 (Bet365)
Sunday 1PM Slate
Ryan Tannehill o196.5 passing yards -110 (Bet365)
Kenneth Gainwell u35.5 rushing yards -115 (PointBet)
Kyren Williams u3.5 receptions +120 (Bet365)
Tyreek Hill o7.5 receptions -120 (BetMGM)
Baker Mayfield o1.5 passing TDs +200 (DraftKings)
Sunday 4PM Slate
Keenan Allen o7.5 receptions +104 (Caesars)
Jake Ferguson u30.5 receiving yards -110 (Bet365)
Brock Purdy u20.5 completions +105 (DraftKings)
Sunday Night Football
Zach Wilson o173.5 passing yards -110 (Bet365)