This is my first time messing with brake lines

Either the line is shot or the flange is. Unless you have a good quality flaring tool I would not just cut a line. Replace the entire line as a piece. Most parts places have them. If you've never done brakes before, this is not a good place to start. Brake lines are hard to flare if you make your own. Chances are high that those flanges are rusted out as well, making it easy to damage more than one line trying to separate them. Then you have to bleed the air out of the system, which can be a challenge for a novice. Decide if you really want to tackle this or take it to a shop. Brake work is bread and butter for just about all shops, so you should have no problem finding a shop with competitive pricing.

those lines may not be the typical one hanging on the rack at auto zoo you may have to order them , go to dealer or have "lines to go " send them , you'll need flare nut wrenches because they are old and rusted , and if the connection breaks or doesn't come loose and have to keep replacing more and more ,, then you have to cap the ends so brake fluid doesn't pour out and then bled the whole system properly when you're done , and hopefully there's no leaks ,still up for it ?,

you don't "cut the line " do you need it for a daily driver ?

Thanks to both and I am ordering the brakes lines. I was thinking I need to replace line from the black object, the the nut., (The L shaped line is what i am refering to .