1. Go to Design --> Edit HTML
2. Thick in the Expand Widget Templates box.
3. Use the code below :
For post title, you can find
.post h3 a {
For blog title, you can find
.titlewrapper {
For font post, you can find under body { , for example (not same for every template)
background:#CFCCC2 url(https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhZzVo-IPAbBpWs3WgC0Srt8crtCsPjUplonrsbnYjW6Hl8gJ0oAtqvWoNo0qTXBHQYej-fwAfqaKGipHrKyAGyK48z28LpRbTQjQ7Qz6hC9q74LpXZoILQq2vsdl3cV3hr7vje3aGLd08/
/headerbg-1.png) repeat-x scroll left top;
font-family:arial;
margin:0;
text-align:center;
}
/headerbg-1.png) repeat-x scroll left top;
font-family:arial;
margin:0;
text-align:center;
}
Generally all fonts can find by this code
font-family
4. You can save your template, if you've finished.