The Skilled feat says (Player's Handbook, p. 170; emphasis mine):
You gain proficiency in any combination of three skills or tools of your choice.
Does it mean I have to choose either three skills or three tools? Or can I, for example, choose two skills and one tool?
The latter. Sometimes, reading using plain English is where the answer is hidden.
You gain proficiency in any combination of three skills or tools of your choice.
(PHB, Ch 6)
The possible combinations are;
3 skills, no tools
2 skills, 1 tool
1 skill, 2 tools
no skills, 3 tools
You can choose any combination that you prefer.
