The upper big teeths ( if u mean the molars) are the important teeths that play role in chewing and must be replaced asap by taking the functional role into consideration.... You can definitely opt for implants provided you satisfy all the criteria's ( adequate bone height, width, accessibility, comfort, patient corporation, time ( 6-8months), etc) that are required for a implant placement. I would advise you to visit a nearby dentist for assistance on the same. A opg mostly will be recommended.

Hello Yes you can go for implants If you visit for a check up then we can see the bone height and width Range for implants range from 25000 to 50000 depending on the type of implant you go for and then the cap

Yes you can opt for implants. Get a cbct of that area done and consult a dentist