They are but this isn’t a JCB.I thought JCB front wheels were usually split rims? You remove the collar to remove the tyre?
Yes take it off. I am not sure if you are showing putting the tyre on or taking it off. With the wheel off on the concrete you will be able to push the tyre into the rim which will give you more to work with. Is the bead fully broken?
If its on the machine then you must have it off the ground, or it will never go on. If its on the concrete then put a wood block under the rim to get the thing in the air, stand up on the tyre and hit it with your club hammer.
If you had the wheel off and washed clean you could lye it on the floor and use your feet too push the part of tyre shown by the green arrows down where the groove is for more room and lever the tyre on at same time