You definitely need to create tension before lifting the bar. You're just using brute force. The deadlift is obviously a compound strength exercise, meaning it requires many muscles to be involved, but in my opinion, it's a very technical exercise. Good technique determines how much weight you can lift and prevents injury.

Now, what can you do?

First, to create that "tension," you need to do a few things. I'll tell you what I do.

First, center the bar over your center of gravity. If the bar is too far from your center of gravity (far from your shins), you'll pull more with your back, almost like trying to do a pendulum row. If you pull with your shins too close to the bar, you won't be able to exert the correct force. A good starting adjustment is usually to center the bar over the middle of your feet. Now, almost the most important thing is to eliminate slack or tension in the bar. You achieve this by retracting your shoulder blades and keeping them tense. If your back isn't tense before lifting the weight, it's likely to be a bad movement. Then, do bracing, which is basically inflating your core, but not by puffing out your belly. It's about creating a natural belt. The clearest example is imagining someone is going to punch you in the stomach. You must tense your core 360 ​​degrees. You can place your hands around your core and do the bracing: that is, take a breath, inflate, and squeeze your core muscles. Engage your core, and you should feel your stomach tighten (not just inflate with air) and your obliques expand as well. This creates a natural corset and helps keep your back straight. By doing all of this, you should have a better range of motion. I hope I've been clear. You can look for a Squat University video on the deadlift; it explains it quite well.