Before we answer these questions, we need to clarify what is meant by the phrase “spiritual gifts”. The phrase is usually used in the Bible [1Cor. 12:1; 14:1] to refer to the miraculous gifts that God sometimes gives to people for various reasons (e.g. the skill and wisdom that God gave to Bezalel so that he could make items for the tabernacle [Ex. 31:2-3]; the superhuman strength God gave to Samson [Judges 14:6]; the ability to prophecy that God gave to Saul [1Sam. 10:10]; the abilities given at Pentecost that enabled the young Christian community to become established [Acts 2:1-6; Eph. 4:8,11-13]). When God gave these miraculous gifts it was for a particular purpose for a limited time (e.g. the spiritual gifts that Bazalel had were for the purpose of producing the Tabernacle [Ex. 31:7-11]; the spiritual gifts given at Pentecost were to initially establish the young church [Eph. 4:11-13]), and once these purposes were complete the miraculous gifts stopped (in relation to the ending of the gifts given at Pentecost, see 1Cor. 13:8-11; also see the answer to ‘Have the Holy Spirit gifts died out?‘). These “spiritual gifts” are no longer around today, although they will be given again when the Lord Jesus returns to the earth [Joel 2:18-32; Heb. 6:5].
With that caveat out of the way, it’s important that we still acknowledge that every good thing we have in life is from God [James 1:17], whether it is rain given in order to make crops grow [Mat. 5:45], our finances [1Sam. 2:7], or even the abilities we have due to genetics [Ps. 139:13] or educational circumstances [Heb. 12:5-13], etc. In this sense, everything we have is a gift from God, including our life [Ps. 104:29-30]!
So, to come to the questions: it’s important to know that everything is a gift from God because it means we will use everything we have to serve God out of thanks for what he’s given. And it’s not difficult to work out what gifts God has given us because he has given us everything! King Solomon recognised this when he said:
But who am I, and what is my people, that we should be able thus to offer willingly? For all things come from you [God], and of your own have we given you. [1Chron. 29:14]
Of course, you may have particular talents, etc., that you are unaware of at the moment. A useful way to help you find them out is to ask some people who know you well and who will give you an honest opinion [Prov. 15:22]; they might be able to highlight things you are unaware of. Some people also find it useful to carry out a “personality test” (e.g. Myers-Briggs Type Indicator; Keirsey Temperament Sorter). Bear in mind, however, that sometimes you might have to work outside of what’s comfortable for your “personality type”.
Also see, ‘How do you know what your purpose in life is?‘