If you can sustain a workout at the same volume and intensity every day, then it's not too much, and you'll be able to maintain your strength at the level necessary to perform that workout (any excess strength will eventually start to dwindle however).
If you're having to reduce the weight on certain days, your target workout intensity and volume is exceeding your capacity to be able to do it every day, and you're heading towards overtraining and a burnout if you keep it up. At least one rest day with no exercise should be inserted between each workout, if not two or three, or six. Depending on the intensity and duration of your workout, and your recovery ability, you might take 2-3 days simply to get back to the strength level you were at before, and the next 1-3 days your muscles are actually getting stronger. So 3-6 rest days is optimal for a high intensity workout.
Keep adding rest days until at the very least you can perform each workout at the same intensity and volume. Ideally, however, you can incrementally increase the intensity (weights used) over time. Maybe not each workout, but certainly once every 3 or 4 workouts you should be able to go up 1kg (that's a conservative estimate, especially starting at lower weights you should be able to do a lot more).
If your gains are still pretty slow, then decreasing volume (number of sets, and number of reps in a set) is also advisable, to aid in recovery. If you really want to do more frequent workouts, ie only one rest day between workouts, then cutting back to maximum 2 sets (ideally 1), and maximum 6 reps per set is the other way to go about it.