Hi, welcome to the forums.
1. Place a start marker in your map.
2. Right click to remove the copy from your mouse
3. Hover over the player start marker and right click to go into "property viewing mode"
4. Change the players Lifes / Health / Start Gun and everything else in there.
As for making a weapon respawn after you lose a life (by default the weapon you start out with will be with you again). But you will have to look in the manual for the respawn properties of the weapon.
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