I believe in Jesus but I am not Catholic. Can I still be Baptized?
Definitely. Many churches (e.g. Baptists) would be glad to welcome you and baptize you.
Yes. Anyone (even a non christian) sincerely willing to do a baptism can perform it on you. With water, the appropriate wording and a genuine intent, it's a baptism.
However, if you're sincere in your relation to God and wanting to make progress, you'll want to ask Him directly (prayer), read the holy scriptures (of course) but also seek the wisdom from fellows, like you would do for any subject. You wouldn't want to reinvent the wheel ? You wouldn't want to struggle with something everyone else learn in a few minutes from a good teacher ?
Even if you only read books, that will definitely lead you in a "school" of thinking. You may change it later if you think you learned everything from it and/or found incoherencies. This is perfectly normal. It's how we seek the thruth.
It seems our Father wants His children to be united. So you may want to join a "school"/denomination while still being open to all your brothers in faith which are sincerely seeking thruth and not judge anyone on where he is on his journey to the truth, being a christian, an atheist, a muslim...
Baptism was performed by John, Christ's cousin, to signify repentance of sins and reconciliation with God (Matt. 3) :
Then Jerusalem was going out to him, and all Judea and all the district around the Jordan; and they were being baptized by him in the Jordan River, as they confessed their sins. ...when he saw many of the Pharisees and Sadducees coming for baptism, he said to them...bear fruit in keeping with repentance; and do not suppose that you can say to yourselves, ‘We have Abraham for our father’; for I say to you that from these stones God is able to raise up children to Abraham"....“As for me, I baptize you with water for repentance, but He who is coming after me is mightier than I, and I am not fit to remove His sandals; He will baptize you with the Holy Spirit and fire."
Some people believe that Baptism is necessary to be reconciled to God. This may be based on Acts 2:
"Peter replied, 'Each of you must turn from your sins and turn to God, and be baptized in the name of Jesus Christ for the forgiveness of your sins. Then you will receive the gift of the Holy Spirit.' Those who believed what Peter said were baptized and added to the church--about three thousand in all.”
Some people believe that it is an outward act (accompanied by an inward faith and repentance of sin) not necessary for salvation, but an act signifying repentance and willingness to embark on a life of obedience to God 1 Cor.:
“But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and by the Spirit of our God.”
Nowhere does it say that you must believe in the doctrines of a particular denomination (Catholic, Presbyterian, Anglican, Baptist, or any other) to be baptized. You need only to repent of your sins, believe in and accept Christ as your Lord and Savior to be saved. The Baptism with Water is an affirmation of this saving faith.
Usually, you are baptized by a member of a particular denomination and introduced or accepted into that church to be in community with other followers of Christ. But that is not necessary to being saved by faith.
If you believe that you are a sinner, that Christ died for your sins so that you could be reconciled to God, that you renounce sin, and that you want to follow Christ, then you are completely correct to want to be (and to therefore be) baptized by water as a lasting symbol of your saving relationship with God.
It should not be hard to find a willing minister to do this, but be ready for Him to ask you how you intend to grow in your relationship to Christ after baptism.