Of course it is.
John 5:24 - “Very truly I tell you, whoever hears my word and believes him who sent me has eternal life and will not be judged but has crossed over from death to life.
From this verse, WHEN does a believer POSSESS eternal life? It says those who believe (present tense) HAVE (as in possess, also in the present tense) eternal life.
So, we KNOW from this verse that the MOMENT of saving faith in Christ, the believer possesses eternal life.
Now, does the Bible teach anywhere that eternal life can be revoked? No.
Now, John 10:28 - I give them eternal life, and they shall never perish; no one will snatch them out of my hand.
This verse very clearly says that those given eternal life shall NEVER PERISH.
So, you now have a choice to make. Either continue believing the very unbiblical heresy that salvation can be lost, or accept the clear words of Jesus Himself about how to receive eternal life (Jn 5:24), and the result of having eternal life (Jn 10:28).
Your choice.