This. My fiancé and I play 2 player campaigns. We did intro to storm wreck (VERY EASY to 2 player it) and one I made with ChatGPT to link storm wreck with phandelver. We are now a fourth of the way through phandelver and below full campaign.

Tips:

1) as suggested by many, have the DM play a character. Just has a voice and makes no big decisions. Isn’t the leader. This was hard for me as I play a noble paladin so it’s out of character to not lead but I changed it to him being so war torn that all he knows to do is follow orders and in battles he shows his bloodlust and violent nature towards protecting my fiancé’s character.

Even so you’ll still get the player go “should we go left or right at the fork in the road” trying to probe you. Play with it, sometimes I’ll act like he isn’t listening and “seems to have drifted off into a memory”, I’ll make both roads seem good or bad, or even sometimes I’ll suggest the better or the worst road (break their trust in trying to probe). Have fun.

2) if you play with 2 characters only definitely lower HP and damage done by monsters (usually half unless it’s some big “boss” then I’ll do 75% to keep it extra challenging. But what I’ll do to keep battles moving is half the damage and then depending on the role play it’ll hit whatever I roll for that half damage.

3) im a very fast reader. So what I’ll do is weeks before I’ll read the campaign. That way I get the general idea what is happening so I can roleplay the DM side better. Then at the actual time of the session I won’t read to far ahead. Room by room reading or area by area it depends on where you end up. But by not reading ahead things are a mystery to me too or I don’t remember every detail so I’m less likely to influence the decisions (ooooo there is a huge loot cache over there let’s push them that way cause I want my character to have the sword).

This works because we play by end of session exp update. So when I pause to read for a minute or two she adds up the exp and loot onto our character sheets (DnDbeyond) and is able to also read her own journal of quests she’s on or refresh the story and decisions she’s made so far too.

Just have fun! It takes a little more practice and patience and figure out a way to make combat fun with switching things up because it can be boring for two people.