Every party needs a couple characters that have the ability to help others out when needed. Giving up a turn in an initiative order to help a brother or sister out is nothing to scoff or sneeze at. In fact, it just might elevate your character to legendary status. Here are a few ways you can help your party members when the group or a player is in (or about to be in) dire straits.
Paladins and clerics have access to this spell. If you have access to this spell, you should use it before every battle. At first level you can choose up to three creatures to bless. That number increases by one with each spell slot used to cast it. (If used as a second level spell, you can choose four creatures and so on.). It allows blessed players to roll a d4 and add the number to any attack roll and saving throw while blessed. It could mean the difference between a hit and a miss, a save or a fail. It is however, a concentration spell. So keep that in mind.
This is a Bard feat that allows you to use stirring words to hype up another player in a given situation. That player gets a bardic inspiration die, which acts like a fate die that they can choose to roll on a check, attack, or save. The inspiration die begins as a d6 and increases at higher bard levels. Unlike Bless, this inspiration die is a one time use and goes away after utilized.
Bards and Druids have access to this spell. You affect a creature with your choice of blue, green, or violet light if it fails a Dexterity saving throw. On a failed save, any attack roll made on an affected creature has advantage, and that creature also cannot benefit from invisibility. Careful with this one as it is a 20-foot cube, and depending on your DM, could potentially affect your party members if you don’t put yourself in a desirable position to cast this spell. It is also concentration, which is something to consider.
If you’re a Paladin or a Cleric and feel like resurrecting someone who has died in the last minute, Revivify allows you to do that. It takes effect instantly and is a 3rd level spell. It cannot bring anyone back who has died of old age, and it also can’t restore missing body parts. So…if a dragon bit your buddy’s head off, not sure how that’ll work. Still, fun!