Most film era third party lenses have compatibility issues with modern Canon digital SLRs. In the past Sigma could “re-chip” the lenses so they work, but I don’t believe it is possible any more.
Even if the do work, they will not be as good as the kit lenses that come with the T7i. The Rebel K2 is a Full Frame camera and the T7i is a 1.6 Crop camera, so your lenses will also not be as wide angle as you are used to.
Mike Sowsun
