Yes, Drowzee does evolve in Pokémon Red.
You cannot get the protector to evolve Rhydon in Pokemon Red version, because Rhydon's ability to evolve with a protector into Rypherior is only available in the latest versions: Pokemon Diamond, Pearl, and Platinum. It is impossible to even get a protector in Pokemon Red version, let alone evolve Rhydon.
level 31
be more specific in your question
Personally i would say as soon as you get gloom evolve it.
beet the league,get the national pokedex get full friendship then evolve it one level
Level the Pokemon you want up to a specific level, or link trade it with another player and it may evolve. Don't forget to get it back though!!!
Tangela does not evolve in Fire Red.
you cannot rent any Pokemon in red version
The same ones as in the blue and red versions ... Kadabra, Machoke, Haunter and Poliwhirl.
AT level 50 this is a good website for all Pokemon and what they evolve into http://bulbapedia.bulbagarden.net/wiki/List_of_Pok%C3%A9mon_by_evolution_family
You cannot evolve Pikachu in Pokemon Yellow, unless you trade it to a red or blue version, and give it a thunderstone there. Once you get it back it will not follow you.
rock smash isn't in Pokemon red version