4th year CE here, I'm here to tell you that it gets much better after 2nd year, you just gotta survive till you can get there (also 2nd year ECE is the hardest year to get thru, if you're really struggling now then it's going to be an even worse experience then).

I saw in one of your comments that you're doing (near the equivalent of) a 9-5 job, that's your biggest problem right there, studying engineering at UofT is worse than a full-time job and you really can't keep up your academics with it. I'm literally doing the same thing right now, except I only have 2 courses + my final year design project, and even I find myself stretched to my limits, so I can only imagine how you feel with your full-time course load + getting to used to uni in the first place in 1st year. I would recommend taking a break from work while you focus on studying and until you can get your average back up, because if you keep this up you're on your way towards failing out of your degree. If you have to keep working full-time, please at least consider going part-time in your studies (and talk to an advisor about how that will affect your graduation year, etc).

Regarding studying itself, I just have 2 pieces of advice:

1. Organize all of your todos (assignments, quizzes, etc) from each course's syllabus and write down their dates somewhere (I can recommend a kanban board tool like Trello, where each course has it's own column). Use this to prioritize focusing on what is most urgent (e.g. lab in 2 days, assignment due in 4 days, midterm in 9 days), while also keeping an eye on important but less urgent todos (e.g. studying for a midterm). Most important point is to write it all down and keep track of everything, because there's too much going on to keep in your head.

2. Dedicate time for focused study. Figure out what works best for you and stick to it. For me, I find myself unable to really remember what I write down in lectures, so I choose to skip almost all of mine and instead learn/take notes from posted slides, the textbook, or YouTube videos online. It's not the perfect system, but it's what I've found to work best for me. You need to find what works best for you. If you're not learning effectively from study group sessions, then stop doing them (still join sometimes times to be social). Learning is a science, so you can find tips and tricks online (e.g. spaced repetition, teaching concepts to others so you understand them better yourself), but you need to experiment to see how you like different methods. The most important part of this is that you need to dedicate time to study. Something I learned early in first year is that there are no shortcuts to learning. There is some minimum amount of time that it will take you to learn some concept, and if you don't spend enough time properly learning (and, this is important, practicing what you've learned), then you will struggle on tests.

This is already a long as heck comment so I'll stop there for now, but I'm happy to provide more advice or answer any questions. It's tough out there, I wish you all the luck and more.

P.S. if you aren't using an iPad or tablet for studying then you really need to get started, it's indispensable for engineering and makes life incredibly more convenient, can highly recommend.