Rct of extruded 21 and 22 recently completed. so should the ortho treatment be started immediately or is it ok to start after 2 months?

In my opinion: If you have enough confidence in the dentist who did the root canal therapy and who will be doing the orthodontics, you should let them make that decision as they are more familiar with your particular circumstances. In the absence of any infection, i would think starting it now would be fine and waiting 2 months has no disadvantage.

Best to wait: You need to be completely healed and pain free, an x-ray will be helpful to show new bone formation which will take at least two months.

No reason: There's no reason why you cannot start tooth movement immediately. Discuss this with both the Endodontist and the Orthodontist.

Don't wait: We in fact will typically bond before extractions to control movement from the moment that the teeth are removed. To prevent tipping and unwanted movement, get the braces ASAP.

Ask Endodontist: It is always important to seek the opinion of the treating endodontist prior to beginning orthodontic treatment involving endo treated teeth. This depends on the reason for the RCT treatment. Always defer to the specialist.

Wait 1 month: Any infection should be resolved, and any restorative treatment should be performed prior the braces treatment. Your orthodontist will continually monitor the situation. Good luck.