in general i agree with Боб Уайтман, however one can also say

Максим хорошо играет на гитаре. Я также играю на гитаре. (stressing the word также in the sentence)

it is true that также can be placed at the head of the sentence if it's used to add new information on the subject

Максим хорошо играет на гитаре. Также он неплохо поёт.

while

Максим хорошо играет на гитаре. Он неплохо поёт тоже.

however in this respect the difference is that также sounds more formal and bureaucratic so to speak
также in many cases sounds awkward if used instead of тоже in colloquial speech and in fact almost never used in it


there're lots of minute tints of difference in meaning and usage between these two and the meaning you wish to convey defines their placement within the sentence.


"ну" isn't embellishment by far and is usually considered a so called "parasite word" which people resort to, not having anything to say, being reluctant to say something or having hard time to formulate their thoughts, a pause filler, if a person uses "ну" a lot, that may mean being tongue tied
it's also used in sentences expressing some sort of reservation or objection in response to someone's statement

Eg.

- Ох и жара стоит сегодня!
- Ну я бы не сказал, что так уж жарко.


it's English "well"


being linked with "а" and "же" it transmits a sense of urgency and impatience to a sentence (this word is used to spur a horse, there's also a same root verb "понукать")

Ладно, с этим мы разобрались, ну а с этим что делать будем?
Ну а я тут при чём?


Ну я же тебе говорил!