If you have a "normal" bike (whatever you mean by that), and want to do BMX style riding, then sure, get a BMX instead. But if you're not interested in tricks, stunts and jumps, then a "normal" bike will probable be more useful to you.
Because they take them to a factory and rebuild their inside. and they do have grip
i think the cable grip holds everything inside the plug as you can tell from the name.
yes of course you can it is like a normal bike
No. Grips and handlebars are fairly well standardized, so pretty much any grip will fit.
Just like a normal grip. Take the old grip off and clean the shaft. Place the tape on. Add solvent and slide the grip on. Search for other questions on replacing grips for full details.
Inside the grip.
Inside the grip.
you want your tires to have the normal air pressure. underinflate tire means wear easily and doesnt have much grip. overflate tire means more grip but less wear.
If the plastic grip inside is broken off and ungripable,you may have to get needle nose pliers,or even vice grip,channel lock to avoid the recession of the post.
There is no one classification of normal for grip strength. Factors vary depending on size of hand and strength of hand.
BMX