A photograph cannot give the final answer
The object in the tread is only part of the story. A tyre should normally be removed from the wheel so the inside can be inspected for secondary damage. The puncture location, size, tyre condition and any evidence that it was driven underinflated all affect the decision.
Sidewall damage is a warning sign
The sidewall flexes continuously and is structurally different from the main tread area. Cuts, bulges or punctures in this area require professional assessment and commonly mean replacement. Do not treat an external plug or liquid sealant as a permanent repair.
Protect the chance of repair
Stop driving as soon as it is safe. Continuing on a soft or flat tyre generates heat and can damage the inner structure even when the outside looks acceptable. Tell the fitter if sealant has been used or if the tyre was driven without pressure.
This guide is general information, not a remote tyre inspection. If the vehicle or location is unsafe, stop driving and seek appropriate professional assistance.