Good Questions...
The Technician License in USA gives you transmission rights for all VHF and UHF Bands using all modes. That includes FM and SSB (voice) according to the band plans. Having a high-power mobile 2 Meter Radio and a good antenna gives you the ability to communicate with others in most areas of the USA. In many areas you will be able to work FM 2-Meter repeaters. You will also be able to use the national simplex calling frequency to call for assistance.
The Technician license also allows you to work the 70 centimeter band which also has a lot of repeaters. If you have a dual band 2 meter/70 centimeter band mobile radio with a good dual band antenna, that gives you access to both repeater networks and simplex communications.
You can get a good dual band mobile radio and dual band antenna for not much money. The antennas for those bands are easily mounted on all vehicles and do not require a lot of expense or room.
I just gained my HF privileges (General License) recently. I have little personal experience with the HF Bands. From my research, 20 Meters is a good band for local, regional, and long-distance communications. There are certainly mobile radios that will work on HF/VHF/UHF bands. These radios are more expensive. The antennas for HF can be expensive to mount on a vehicle for mobile operation.
For my Jeep I just purchased a Kenwood TM-271A mobile 2 Meter radio. It is a mil-spec ruggedized radio. The cost is under $180 delivered. I have that coupled with a 5/8 wave antenna. The combination of 65 watts of power with a good 5/8 wave antenna gives great performance and reach.
For base operations, I use that rig and antenna presently with an Astron RS-20A power supply. Works very well. I am going to mount a base antenna on my house in the near future. I can power the radio from a battery during power outages.
The Technician license is easy to earn. Read the manual through from cover to cover at least once. Pay attention to the rules and operating procedures. The question pool and answers in the back of the book are exactly the same questions that the actual license exam will be taken from. Exactly. I would recommend that you study for the exam this way: Highlight the correct answer for each question. Use a sharpie to blacken out the wrong answers for each question. That way your brain doesn't even see them and register them. Then rote memorize the questions and correct answers. Start doing this about 2-3 weeks before the exam date. Once you have a question down cold, then use another highlighter color to mark the question. Then keep studying the questions that you do not have cold. You can take practice exams on
QRZ Ham Radio. When you are consistently scoring 85 percent or so, you are ready for the exam. THen, once the exam is over, go back and read the book again. This time you are trying to learn the craft, not pass the exam! Join a ham club. That is where you will learn the most. Do some research, buy a rig and get on the air.
Best Wishes,
KD6SNH