Toddler problems (long please help 😩)

Please help me I am struggling..

I have a toddler, he turns 2 next month and overall he's an amazing kid. He was a super easy baby compared to his sister right now and he's just really sweet and super independent with his moments of difficulty, usually because of a milestone he's going through.

We just had to convert his crib into a bed because he was able to put his leg over the bar to use it as leverage and we didn't want him to get hurt trying to climb out. It's been about a week since we did this and I am absolutely miserable. The first night he was okay and slept the whole way through the night, the second night he got up a couple times and I figured he might have rolled out of bed so I orded a toddler bed rail and installed it the next night (nothing was available in the area immediately).

This however was not the issue because upon installing the new baby monitor (we had no camera before) the same day I learned he just wakes up in the middle of the night (typically around 2am) and gets himself out of bed so he proceeds to go to the door and cry. I'll go in and calm him and get him back in bed, but he ends up getting up a couple hours later so then we're up and 4:30-5am instead of the usual 7am since at that point he absolutely refuses to lay back down. I feel like he was waking up at night before but since he couldn't get out of bed he just went back to sleep with no fuss.

Did I transition him too soon? Or do I need to possibly cut naptime down more? I don't wanna take it out completely cause he still crashes mid-day, but I have noticed naptime has been harder to get him down for. He currently naps for 1hr because 2hrs was too much and causing him to get up earlier.

We're in his room by 7:30pm for bed and he's typically out before 8pm, he doesnt fight it and bedtime is pretty easy more often than not . Do I need to adjust bedtime? Do I make it later? Earlier?

I don't know what to do and I'm so friggen exhausted because I'm basically up by 2am because his 2month old sister wakes up between 2am-5am to be fed. I'm only sleeping 2-3 hours a night because the 2mo is really hard to get down for bed, she really fights sleep (she'll close her eyes and doze off for a brief second before starting to cry and wake up again). My partner tries to help as much as he can but it's been really hard on both of us. I am drowning right now and I need help.

What do I do?