I Learned 4 tenses today. I Learned 4 tenses today.

You can capitalize it as either "I Learned 4 Tenses Today" or "I learned 4 tenses today", but you shouldn't mix capitalization. The first version is the more correct version (titles are always capitalized) but since this is social media it doesn't really matter.

Since I found the englishpage.com yesterday, I started to learn tenses. Since I found englishpage.com yesterday, I started to learn tenses.

Since I found the englishpage.com yesterday, I started to learn tenses. Since I found englishpage.com yesterday, I started to learn tenses.

Today, I'm learning below 4 tenses.: Today, I'm learning 4 tenses:

You don't need to add "below" if you have a colon because then we can assume that there will be a list following it. If you wanted to add "below" anyways you could say something like "Today, I'm learning 4 tenses. Listed below:"

Today, I'm learning belowthe following 4 tenses.: Today, I'm learning the following 4 tenses:

1. sSimple present: 1. Simple present:

Theis website is so great. This website is so great.

You'd say "this" because you're referring to where you are right now.

2. pPresent continuous: 2. Present continuous:

3. sSimple past: 3. Simple past:

yYesterday, I found theis website. Yesterday, I found this website.

4. pPast continuous: 4. Past continuous:

At tToday's at 3 PM, I was learning tenses. Today at 3 PM, I was learning tenses.

At 3 PM today's 3 PM, I was learning tenses. At 3 PM today, I was learning tenses.