Jisho

Okay, so from my understanding, the sentence goes as follows:
The first part is read as "Boku wa". and it means "As for me", or "I am". In this case, I believe that it's just introducing myself into the sentence as the topic, or what the sentence is all about. So the first part is just "As for me". However, when paired with the next part, which reads "kokoro no soko", I believe it turns from "As for me", to "As for my", in order to show possession of the heart, "kokoro", that has been introduced. Sentence now reads "As for my heart". But hold on, what about "no", that thing right in the middle of the two kanji? It serves as the possession particle, and in this sentence, the word/kanji behind it (or to the left) is the possessor, and the word/kanji in front (or to the right) of the "no" particle is the possession. Now, taking that into account, the "possessor" is our heart, and the possession is "soko", or "the bottom". Therefore, the sentence can now read, "As for my heart's bottom" or more practically "As for the bottom of my heart". Alright, now let's move onto the next part. We start off with "kara" which translates to "from", which shows origin. For reasons beyond me, "kara" or "from" is in front of "As for the bottom of my heart". Taking that into account, we can now add "kara" or "from" to our sentence, making it： "From the bottom of my heart". Okay, now let's move onto the word next to "kara", which reads "Kanojo". This word translates to "her" or "she". We can't really do anything with that right now, unless we have a particle, so we can just keep in mind the simple fact that now some woman is apart of our sentence. Sentence now reads, "From the bottom of my heart,she...." if we add "kanojo". Alright, onto the last part. Okay, so "wo" is, and bear with me cause I didn't get it at first, the object marking particle. This fundamentally means that whatever comes before this particle is the object of the sentence. What is the object you may ask? Well, it is what is being acted upon within the sentence. So, "kanojo" comes before "wo", so now we know that something WILL happen to this girl. This won't remain a mystery for long, because if we look in front of the object marker, we see the verb "to love". If you haven't figured it out already, the thing that comes BEFORE "wo" is the object, and the thing that comes after "wo" is the action being done to the object, which is a verb. But wait, now you may be asking, "wait, who loves her then??" And I am here to tell you that it is us! You know why? Because we are the topic of the sentence, which was made clear by the topic marker "wa" in the beginning of the sentence. So, with all this wonderful knowledge, we can now read the sentece as " I love her from the bottom of my heart", or even "From the bottom of my heart, I love her."
Listen guys, I hoped this helped :D
Bear in mind that I am not the Japanese master, so if I missed or messed up something, PLEASE let me know, I'd love to expand my knowledge through my mistakes. :D