It depends on the technique chosen by your dentist and that fits your situation. Usually in standard procedures it takes a minimum of 3-6 months for the implants to integrate and at least few weeks for rehabilitation.

There is no need for any of those. General anesthesia is on recommended in cases of sever dental phobia

Age is not a limiting factor for dental implants. Dental implant cases are documented since ages 18 and above. If your health allows, you can have dental implants with no age limitation.

Yes! And even stronger. Bite's strength is found to be even doubled with dental implants compared to natural teeth.

Most patients say the procedure was even easier than an extraction of a tooth. You may feel no more than a slight discomfort, thank to modern local anesthesia.

Some factors may reduce success but are not contra-indications, like controlled diabetes, alcohol drinking, heavy smoking.
There are situations when dental implants are contra-indicated and not allowed. Advanced osteoporosis, uncontrolled diabetes, people that had radiotherapy in the head and neck area and people that had bisphosphonate injections.

Yes, in most cases it is possible.

The signs for a failed implant include the appearance of swelling, pain and mobility of the implant.