This is a very ambiguous question. You have asked which "form" of a verb the first person subject will take. Let us clarify first.
English verbs have 6 tenses and 3 forms. The 3 forms are as follows:
Basic, Progressive, and Emphatic
The 6 Tenses are as follows:
Present Present Perfect
Past Past Perfect
Future Future Perfect
As the above post mentions, subject/verb agreement is always observed when conjugating verbs with their subjects (i.e. putting verbs in the proper "form" as you say)
Now, let us use a verb as an example - to learn and conjugate it in all its forms and tenses. Then, you can select which one answers your question as you will see which helping/auxiliary verbs are used with the main verb, learn.
Present Tense-I learn Present Perfect Tense-I have learned
Past Tense-I learned Past Perfect Tense - I had learned
Future Tense - I will learn Future Perfect Tense- I will have learned
Present Progressive - I am learning
Past Progressive - I was learning
Future Progressive - I will be learning
Present Perfect Progressive - I have been learning
Past Perfect Progressive - I had been learning
Future Perfect Progressive - I will have been learning
Present Tense - I do learn Past Tense - I did learn
[There are only 2 tenses in the Emphatic Form]
To continue this discussion, it is important to consider what import the sentence has. For instance, is the sentence supposed to convey something one is doing right now? Then, use the Present tense, Progressive form. [e.g. I am writing this.]
Or, is it meant to convey a regularly recurring action? Then, use the Present tense, Basic form. [I write often in my journal.]
Forming the tenses and the various forms of verbs involves using one of the principal parts of the verbs [present -learn, present participle-learning, past - learned or past participle-learned] These principal parts are used with the auxiliary verb to be in the progressive form and the auxiliary verb to have in the perfect tenses of basic form and progressive form.