Tubes aren't expensive... until you start changing them yourself. Then , the learning process will involve pinching at least one, if not more, and having to do it all over again, when you air up the tube and find it has a hole in it from pinching the tube with the tire iron... or the long screwdriver, or Car Tire Iron lol... I personally, would take your complete rim/tire assembly off the bike, and roll it straight to the trunk of your car, or bed of your truck, drive it to your favorite motorcycle tire shop, and let them do it. If they hole a tube, they are responsible...
Now this isn't to say that you can't do it, but your learning curve might be a bit steep. I have read your threads, and you will persevere, but it may cost you a bit. First, you need a GOOD set of motorcycle tire irons, and don't go cheap here. Get the longer ones. Then, the Astro... er, RUglyde tyre lubricant, and an area to work in. If your front tire has a disk, you want to be sure that it is held above the ground with a couple 2x4's or 4x4's to keep you from warping it on the concrete. It has happened, then you would need a new disk.
Personally, for the $20 a shop will charge you for labor, it's well worth it. Take them your new tire, and make sure they have a tube that fits it, if not, get them one.
Charlie