"AてもB" is "B, even if A." That is B is still true in case of A (so is certianly true if A is not the case).
You can form a ても-clause be adding も to the verb or adjective te-form. With な-adjectives and nouns, you have でも. Note that verb たら and ても forms look very much like each other, but adjective たら and ても forms look quite distinct.
verbs: かう -> かっても
い-adjectives: かなしい -> かなしくても
な-adjectives: げんき（な） -> けんきでも
nouns: がくせい -> がくせいでも
Note: The ても clause itself does not have tense. It can be followed either by present tense clause, or by a past tense clause.