There’s some things beginners need to do differently than advance lifters.
First off, it’s best for beginners to chose ME lifts very similar to the competition lifts. Beginners need the practice. Like if your quads are your weak point, then pick high bar narrow stance squats. Still go to PL depth and use your PL form. I stick with the box b/c it doesn’t beat up my joints so much when going heavy, but losing it has helped raw lifters so you might wanna try both. I wouldn’t even use much accommodating resistance for ME work.
You should be working up to 3-5RM maxes instead of 1RM’s. As Osu said, you need to build your base and that’s done with volume.
FlatsFarmer brings up a very good point. Building work capacity is extremely important in this type of training. A good way to start is by doing an extended warm up before your main lifts DE and ME day. This could be some hypers or chest flies or push downs. Something that toes the line between warm up and work set and then after a few weeks actual work sets.
Also doing ‘mini-sessions’ that are 15 minutes to 30 minutes absolute max. This could be conditioning oriented, building up a weak muscle group, or re/pre-hab work. Start with one a week. Over many months to years, you can build up to doing these almost every day.
You have to train the stretch reflex for the squat somehow especially if you’re a raw squatter in my opinion. This can be done with either free squats or plyometrics in my experience.
To directly answer your question about overloads, they’re not a must have but may be more optimal for an individual in particular situations. Yes, I know that’s a bit of a non-answer answer but it’s the truth. The key is to use them sparingly so you don’t burn yourself out or overtax your joints. My go to’s are squats with chains, block pulls, and 3-board bench press. But those might not be the best for you. Just make good training log and see how things work out.
Check this thread out. It’s pure gold: