What kind of things should I be doing as a squad leader?

The list is longer than the internet. The best to start, honestly, is the NCO Creed. Live by that. With that in mind, look at the mantra "Mission, men, myself." Mission comes first, always. Take care of your men (and women). In your spare time, take care of yourself. But you DO have to make the time to take care of yourself - burnout is real, and it leads to crappy leadership.

You show on RP as a SPC, so you should be able to remember, quite vividly and quite easily, what being a "joe" feels like. Remember all the things that your squad leader did that ticked you off? Now don't do those things. Except, of course, that now that you are in that position, you may start to realize that some of those things were necessary. But when you find one of those things, a little communication goes a long way. "Hey folks, I know this sucks, but here is WHY we have to do this." And always make it a "we," you are in charge, but still part of a team.

I have seen more than a couple questions from you on RP regarding things. That is great - there is a phenomenal brain trust here. But don't forget that you have a BETTER (usually) brain trust at your unit. It is better, because the other leaders around you at your unit will understand the ground truth for you, and can give tailored advice, far better than us armchair quarterbacks. Use your local leaders. Ask your peers for advice. don't be afraid to schedule time with your PL and PSG to plan, strategize, organize, or just learn. Each leader should be looking two echelons down. That means that as a squad leader, your PSG and PL have the primary role in teaching, coaching, and mentoring you, but the 1SG (and CO) ALSO has a role. Do not abuse this, but the 1SG is also there for mentoring. (Always go to and through PSG first, but don't be afraid of the 1SG - respect, definitely, but don't fear.)

Final note: You are in a squad leader position as a SPC. This is a VERY difficult line to walk. You have far more authority than your rank can support. Don't act or think like a SPC. You have to provide the leadership to your subordinates. BUT, you can't get too big for your britches either. A Team Leader who is a SGT still outranks you, even if you have a higher position. You have to learn when to exert the authority of your position, and when to acknowledge that you still are only a SPC in rank. I would recommend talking to your unit about at LEAST pinning on CPL to give you that NCO authority. Good luck and godspeed.

Get yourself into a Leadership course as soon as you can. In the mean time, you know how you were treated as a subordinate. Treat then as you would want to be treated. Respect the fact that you now have several new personalities and their issues to deal with. You're not their buddy. Act accordingly. Don't let it go to your head. Never be a "because I said so" type of leader. If your Platoon Sergeant tells you something needs to be done, own it and put it out their like it is coming from you. It's easy to say " come on guys, SSG Doe wants us to go do police call" instead of saying Soldiers we need to go out and do police call. You'll do fine and don't be afraid to speak with your leadership and get their points of view. They put you in that position for a reason.

Learn how to delegate. You do not have time to do everything yourself, so task a trusted agent. That doesnt mean you can not help them do it to get the job done, but focus your help on what priorities are based off commanders intent and priorities. It does mean you inspect and verify the task was completed to standard by said trusted agent. You can always delegate authority but never responsiblity.
Notice I didnt say the lieutenants intent
He/She doesnt get one because they are not in command, but their priorities should mirror the commanders, if they dont you need to have a talk with the lieutenant to understand why.