Guys, will I still make gains if?

Anonymous
I'm not being sexist, but I'm asking the guys because they usually do give better workout advice when it comes to weight training.
So lately, I've just been doing three sets of 10-12 reps. If I can do more than 12, the weight is too light and if I can't get to 8, the weight is too heavy.
I train upper body and lower body twice a week. Upper body is back, tris and bis, chest and shoulders. Lower body is quads, hamstrings and glutes. I just do abs whenever I feel like it. Then, I do cardio twice a week. I'm very ectomorphic and it's hard to gain weight so I'm trying to steer clear of too much cardio.
Anyway, I hear a lot of high reps/low reps mumbo jumbo and I don't know what I should be doing. So, I was thinking I should do my usual 12 reps on one day, and start lowering the reps on the other day. Of course, while changing the weight to suit the reps.
So, I usually do lower body on Monday and Thursday. Using the squat as an example, if I do a 30 kilo squat at 12x3 on Monday, and then on Thursday, a 40 kilo squat at 6x3, will I get bigger (what I want)? All while doing an hour of total body pilates twice a week to get that endurance in there, too.
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+1 y
Hellloooo I need more answers!!
Guys, will I still make gains if?
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