I was suppose to get a tooth implant but now they want to close my gap with braces. is this ok?

Sure it's OK: There's nothing better than your natural teeth, even when compared to implants. If you were naturally missing a tooth, then the volume of bone in that area may not be adequate for an implant, necessitating additional surgeries. Trust your dental providers... they have many, many years of experience in these matters.

Closing a space: using braces is very possible. However, placing an implant to replace a missing tooth can also be a good treatment plan as well. It really depends on what tooth is missing, how long it has been missing and ultimately will the bite be functional and will the end result be pleasing( esthetically) You should have a thorough discussion with your orthodontist about the pros and cons.

Ask a pro: ask a fully qualified Orthodontic Specialist. Sometimes closing one space can open another one on the other side. Sometimes moving a tooth can compromise your "bite." It's a complex question. See a tooth-moving specialist, rather than a GP, for advice. Sometimes space closure is best, sometimes tooth replacement is best. Most often a combination of the two is ideal.

Yes, no, maybe?: There is no one right answer, at least over the internet, sight unseen. This needs to be evaluated by a General Dentist or Prosthodontist in consultation with an an Orthodontist for the best long term outcome and prognosis. If you are truly 16 years old this is an especially important decision. You might want to consider a second opinion from trusted and recommended professionals in your area.

The rule of thumb: Are there other reasons to have braces like multiple spaces, crowded teeth, overbite or malocclusion? If there are no other reasons for braces, an implant is a great and best choice.

Sure: If they can fully close the space where you were to get an implant that may be a great solution and save you the money and pain of an implant. However, the fact that you are asking here indicates that the plan the orthodontist has for you was not particularly clear to you. Go back and discuss it with them so you understand and agree with the course of action.

All depends: Your question is too simple to answer w/o details. If you need an implant, it is important to have orthodontic treatment BEFORE getting an implant. The implant is fused to your jaw bone, therefore can never be moved via orthodontic treatment. Speak to your dentist, orthodontist, and oral surgeon about your comprehensive treatment plan.