Exits are the toughest decision in trading and there can't really be a single right way but I can tell you my way. I never set a TP and never close a trade, they only close when a SL is hit (unless I need to close an oldest trade to release capital for a new one). When I have multiple trades on the same chart in parallel, all the trades close at the same time. Obviously, the worst result is for the most recent trade, which is a total loss, but the others are less painful. The loss on the last trade is the same capital as the risk on the very first trade. The next to last suffers a break-even, the older trades all make a profit.
e.g. A nice day-dream is to one day have 10 parallel longs on the same pair or index. Let's say Trade 1 had a TA-based SL 96 pips below entry, so my initial risk was 96. When Trade 1 gets to +96, I move its SL to its' entry and open Trade 2, also with a 96 pip SL. And keep doing that forever. Every 96 pips up, open a new trade with a 96 pip SL and move all the other SL's 96 pips higher. Maybe when to want to open Trade 11 you're out of capital, so close Trade 1 to release it. Otherwise, keep letting all the trades run until there is a 96 pip price drop, in which case they all close at once.
Onwards and upwards.