Here is a picture of Prophet Ibrahim (PBUH) footprint near the Kaabah
Is there any evidence that is definitely footprint of Prophet Ibrahim (PBUH)?
I am unable to validate the authenticity of this picture. However, it has been reported by the sahabi Anas ibn Malik that the prophet Ibrahim's footprints had already been worn out (from people touching it) in his time. This was 1400 years ago, so I doubt that there are any of the original markings left in this day and age.
Anas bin Malik's report is mentioned in Tafsir Ibn Katheer, specifically in the commentary on Al Baqarah 1:125. It is in page 417 of this PDF version (Arabic).
Yes, according to Quran:
وَإِذ جَعَلنَا البَيتَ مَثابَةً لِلنّاسِ وَأَمنًا وَاتَّخِذوا مِن مَقامِ إِبرٰهـۧمَ مُصَلًّى ۖ وَعَهِدنا إِلىٰ إِبرٰهـۧمَ وَإِسمـٰعيلَ أَن طَهِّرا بَيتِىَ لِلطّائِفينَ وَالعـٰكِفينَ وَالرُّكَّعِ السُّجودِ
And [mention] when We made the House a place of return for the people and [a place of] security. And take, [O believers], from the standing place of Abraham a place of prayer. And We charged Abraham and Ishmael, [saying], "Purify My House for those who perform Tawaf and those who are staying [there] for worship and those who bow and prostrate [in prayer]." [2:125]
and this is now near the house, behind which (at least, Shia) Muslims pray after Tawaaf.